Well for that to be valid conventional outright purchasing needs to go away.
Until then it’s nothing but a conspiracy theory.
If everything is part of one of a few subscription services..... why would anyone still use conventional outright purchasing? How would that itself not become so niche that only a handful of people would bother with it?
Nothing to do with "conspiracy theory" it is a logical inevitability. M$ has tried to do this a few times for their own software and will keep trying, other major software developers has tried or already has done so..... games because of their nature of not requiring yearly updates will be the last natural holdout.
I do not see any logical reason for this to be crackpot especially since it is already happening the first having been steam locking access to a profile that can be revoked instead of physical media.