SO many people constantly tell us that the reason the LGBT community has rights, is because "trans women of color started to riots at Stonewall." This is a MYTH.
My question though, is WHY do the progressive leftists feel the need to rewrite history? What do they feel they gain by doing this?
Because they believe if they rewrite/control history, they get to write their narrative going forward without the contradiction from the past and have more control.
Have you ever heard someone say,"That's the way we have always done it." That is why they do it.
Francis Bacon said, "Knowledge is power." But then that might mean the lack of knowledge is servitude.
Did a little research. From what I can tell, what you say is a myth. But it's a myth because I'm not finding widespread evidence that anyone is saying it, because this notion of history being re-written simply doesn't have teeth.
The transwomen of color you refer to are likely Marsha P. Johnson and Sylvia Rivera. I found no other transwomen of color come up on my searches for "transgener stonewall riots" (if I'm wrong, please let me know and I'll amend my search.
That they were at stonewall is not in dispute. Yet, in their own words, and long before the woke movement, they deny starting the riots at Stonewall as seen in this 2019 WP article:
But in 1987, Johnson told historian Eric Marcus that she didn’t arrive until “the riots had already started.” And in 2001, Rivera said she was at the Stonewall Inn with a boyfriend when it was raided but that she wasn’t the first to resist. 
In this 2019 article from the NYT, they are not credited with starting the riots but merely being key figures at them:
They are also believed to have been key figures in the June 1969 Stonewall Uprising who fought police as they raided the gay bar on Christopher Street. 
We even have the following from USA Today with the provocative title "Why we owe Pride to black transgender women who threw bricks at cops" again from 2019 (because of teh stonewall statues). But as we read the article:
Many in the LGBT community credit transgender activist Marsha P. Johnson for throwing the first brick or shot glass that sparked the riots, though Johnson said she didn’t arrive at the bar until rioting was underway. Nevertheless, her role is hailed.
Again, the article recognizes the "urban myth" of her throwing the first brick but immediately states that Johnson refutes that and that her role, whatever it was, is hailed by the community.
So on this first pass, in three arguably liberal magazines, the "transwomen of color' boil down to two women, Mss. Johnson and Rivera... while the "started the riots at Stonewall" is soundly refuted.
For better fidelity, I then did a more exact search under your proposed myth, searched under "trans women of color started to riots at Stonewall". Here is what I found:
The first hit gives credence to your thesis. From PBS Newshour extra in 2020
This month comes on the 51st anniversary of the Stonewall Riots, a series of protests started by a black transgender woman named Marsha P. Johnson >
This is clearly wrong. So why the mistake? One need only read down further to the author
Today’s Daily News Story was written by EXTRA’s intern Carolyn McCusker, a senior at Amherst College.
Written by an intern. A college student. Basically a D+ term paper. Not very credible nor reputable, certainly not on the level of WP, NYT, or USA Today.
Next is a hit from Inverse in 2020. Don't know the magazine but I include it non the less. It says
On June 28, 1969, police raided the Stonewall Inn, a meeting place for LGBTQ+ New Yorkers. When they demanded to do sex verification checks on trans women, a spontaneous protest broke out, and at the forefront of those protests were trans women of color like Marsha P. Johnson and Sylvia Rivera. Pride itself owes its very existence to a riot, and it took radical acts of change to just start the conversation about LGBTQ+ issues in America, a conversation that continues to this day. 
Here again, they do not reaffirm that they started the riots and while they do speak of other transwomen than Mss. Johnson and Rivera (as of course there must have been), they do not credit them with starting it or throwing the first brick.
In conclusion, my very quick and dirty google search turned up one article that supported your thesis and that written by a college student. All the rest (all from 2019 to 2020) clearly state that transwomen were at stonewall but that Mss. Johnson and Rivera did not start it.
As such I found no evidence that there is a massive rewriting of history since the history has been clear since 1987 and 2001, when the two transwomen purported to have started the riots literally said they didn't start it and yet they were there and were integral parts of the community and the movement
The problem progressives have with the early gay rights movement is exactly the same problem they have with the second wave of the feminist movement - both are too white. The once revered Gloria Steinem is often criticized and rejected by postmodern feminists who see the movement of her day as too white and too conservative.
Feminists like Camille Paglia are detested by progressives for their conservative views. Gay rights are not about gays, just as feminism is not about women. As Paglia observes so brilliantly in her book “Essays”:
Ayn Rand was the kind a bold female thinker who should immediately have been the centrepiece of women studies programs, if the latter were genuinely about women rather than about a clichéd, bleeding heart, victim-obsessed, liberal ideology that dislikes all concrete female achievement.
The woke-left has a similar issue with pioneers of the gay rights movement, because many men were embarrassed by the excesses of their own community, including its ridiculous alliance with openly pedophile groups, who for a time were permitted to march in pride parades. The Mattachine Society of New York — which advocated for respectability — is an embarrassment to the left, which sees them today as conventional, white, sell outs.
So Stonewall had to be reimagined. Over the past few years, for example, Wikipedia has added woke buzz words like “poor, marginalized”, “homeless youth”, and “anti-transgender discrimination” to its Stonewall page. Progressives have also searched records diligently for any mention of non-white men in the crowd, and two women of colour have recently been cast in the starring roles in the fantasy version of Woke Stonewall: Sylvia Rivera and Marsha P. Johnson. Stonewall, like a modern TV series, has been tokenized with casting diversity.
The left is not just tearing down statues. It is busily deconstructing all of our history into something new and false.
How many is "so many"?
If you are referring to a handful of Twitter twits or InstaGrab influencers, then more fool you for paying attention to the intellectual lowest common denominator.
If on the other hand this is part of established School curriculums or enjoys wide dissemination in various media outlets, then you have a point.
The extent of the problem will moderate the extent of the solution.