What's going on with Google being extra stingy seems to correlate well with the AI boom (curse). I suspect there are companies running ruthless bots scraping TBs of videos from YouTube. Not just new popular videos that are on fast storage, but old obscure ones that probably require more resources to fetch. This is unnatural, and goes contrary to the behaviour pattern of normal users that YT is optimized for.
I think AI-companies abusing the internet is why things are getting more constrained in general. If I'm right, they deserve the bulk of the blame imo.