At my recent heaviest I was nearing 150 kg which is rather substantial. I've been hovering between that and 130 for the last 4 or 5 years and during that time has cycled most days, every day through many periods. I ride a mix of gravel and road, no actual mountain biking but occasionally rooty and rocky.
During that time I rode bikes spanning everything from a lightweight thin walled Explosif, to various tange ultralight to early 2000s alu. All frames are fine. Now was I riding stuff where it is likely I would get air time, it might have looked different - but even so - it would likely be fine. When recreational riding in the woods and on fire roads, you're simply not going to be getting some sort of catastrophic failure. Yeah, with some lighter frames it may be ridden over the fatigue limit for a good while, but even so will likely be replaced before it ever gets to that point. They're obviously also very conservative about load capacity, most manufacturers, because they have to be. As long as you're not picking an old knackered paperthin race frame I would say you are golden.
It pisses me off to no end when cycling is gatekept from fellow fatties. When I got back into cycling after many years of only hiking, I was very heavy and was told the only thing that'd work was a... Worksman. ******* scummy to imply all a fat person can ride is a fecking utilitarian industrial strength boat anchor. It put me off for a long time. I was then recommended Surly, there a love story began. Then I realised they're just bog standard chromoly frames and realised I'd been blinded.
All in all I've never felt that worried riding any of my bikes really.
About wheels, I do agree that it is where a lot of that stress will be going. Good place to spend money or go for a custom build. But even so I haven't gone through many wheels. And I always bought the cheap machine assembled deore hubbed ones. The key is to try and keep at a decent tension consistently, because you don't want them to fatigue faster. That has been my main issue. I have many older wheels where a full rebuild really is the way to go. Yes yes yes on the tyre pressure brought up, I've always had issues running lower pressures, being bigger just means accepting that you gotta beef up that tyre.
The most important thing, I'd say, is getting a nice position for the rider dialed in and get a good sturdy saddle they like.
Happy riding.