Sponsors are all about the PR. They're looking at it from their end, being associated hurts their image. Which is why they choose to do this now with the current social situation. They weren't threatening pulling out of sponsorship before when there wasn't a backlash.
I believe you have this backwards.
The timing of this only allows for these companies to capitalize on the current socio-political situation in the US. This is why they chose to do this now.
For example, while Nike made a victory lap by removing the WAS team name from its site filters, it is still going to supply the team with equipment at a great discount.
FedEx will continue to hold the naming rights to the WAS arena.
And Pepsi will remain the official provider of soft drinks during games.
Just empty gestures to get on the right side of the investors here.