Meta created and support React
An engineer who worked at Meta did some stuff on his personal Github and managed to get them to adopt it. They weren't being innovative, they got someone else to do the prototyping and then brought it in.
Much like the same conversation about other large organisations that buy to "innovate".
...Pytorch
Didn't they just hire some of the maintainers of Torch7, who had started on the rework of implementing lessons learnt and migration to Python? So you while you could say they "created PyTorch", it would be quite misleading.