This is not accurate. Most large contributions up to at least 3.6 have come from individuals, many of whom left or went silent because they could not stand Python core or its development practices.
GvR has contributed very little while at Google.
Even with asyncio most contributions came a) from independent developers who fixed all the mistakes and then b) another non-FAANG developer who augmented it substantially.
FAANG provides power hungry politicians who go for every title and position of power in Python core and the PSF.
The Python speedup project is the first of its kind and so far is based on decades long independent work of Mark Shannon.
I doubt than any JIT expert at Microsoft would want to get involved with PSF politics (career risk), especially because F# and C# are better languages.
(The no-gil project of Sam Gross is the second of its kind, but is unlikely to go in because NIH politics.)
In which case, they actually have, on multiple occasions, including currently Microsoft being one of the biggest contributors to Python core.
At one point Google employed Guido and he worked on Python there, and I believe they also have made alot of contributions to core.
Can't speak as much to Meta or Netflix though, simply don't have the knowledge
Its an architectural problem, more so than a money one