Interesting point, yeah. Does it need to be a PR company, though? If I bought NVDA I'd also be incentivized to talk about how healthy the company looks.
Personally, I don't think it's (paid) PR per se. Call me cynical but I'm fairly sure TechCrunch has always been mostly lightly laundered press kits. This is, of course, something that is endemic across most trade or trade-adjacent media.
I don't think any company will be able to hold a significant monopoly in the space for the simple law of economics: high margins (especially combined with high absolute volumes) attract competition.
And the wider the margins and volumes the more competitors have incentives in making gigantic investments.
[1]: https://www.paulgraham.com/submarine.html
And the wider the margins and volumes the more competitors have incentives in making gigantic investments.