Meta and Google have done more for open source ai than anyone else, I think a lot of antis don't really understand how computer science works so you imagine it's like them collecting up physical iron and taking it into a secret room never to be seen again.
The actual tools and math is what's important, research on best methods is complex and slow but so far all these developments are being written up in papers which anyone can use to learn from - if people on the left weren't so performative and lazy we could have our own ai too