AdBlocking is 100% OK, that part is correct for sure. Ad networks (including Google's) routinely serve up scams and malware: It is foolish not to use a browser with a fully functional ad blocker at this point (i.e. avoid Chrome, use Firefox with uBlock origin).
As for whether Google approves: Fuck Google! They have been serving up malware and scams in their ads. Their opinion should be irrelevant if you have any interest in protecting yourself, they have repeatedly proven they cannot and should not be trusted.
They aren't: This is 100% state dependent. Some states have extremely permissive laws allowing you to carry anything from a switchblade to a greatsword if you want.
Steam Deck is great, 10/10, would recommend, but you could also just load Linux on your old system and keep using it.