Noah is undoubtedly a scumbag, Nielsen is a little more tenuous. I don't think it's just something as simple as different political beliefs, some of the stuff that she was retweeting was abhorrent:
I just think there's a HUGE chasm between someone who is supporting conservative values (which I have no problem with) and retweeting pro white supremacy and real ignorant shit regarding protests (which can fuck right off) from a while back. It's just a horrible look, I can see why WoTC cut ties with her. You can't try to present yourselves as an inclusive game open to everyone and then keep deploying work from someone in stark contrast to your proposed ideals. I think they gave her a grace period to see what was actually up after stuff creeped up a while back and then just found out more unsavory stuff before calling it off. It didn't help that she topped it off by sending art a year back, personally, to some loony bin conspiracy YouTube channel that loves regurgitating bullshit and spreading misinformation. She may not have been outright stating that she was in favor of everything ignorant she was retweeting, but most of us weren't born yesterday. There's no subtlety here. Reading between the lines makes it pretty obvious where she is on the political spectrum.
People who bask in extreme ignorance harmful to others should absolutely be called out for it, especially those that proactively support denying the rights of others. She either believes and agrees with (and by extension promotes) anti-semitic, racist, and transphobic stuff based off what she's following and retweeting (there's more stuff, I'm just not gonna dig it up again).
It's a shame, but being a great artist doesn't give her a pass in supporting extremely ignorant bullshit without potential consequences. I'm not about to throw away the cards and prints that I have of her art, but I'm absolutely not buying anything going forward if I can avoid it.