The problem with threads like this is that there is always the underlying assumption that someone is giving up something by shooting higher poundage.
If you can't draw your bow back properly without convulsing, you can't shoot consistently over the course of a few dozen arrows, you can't shoot accurately, and you can't shoot without injuring yourself, you are definitely overbowed. That can be said for any bow - compound or trad - and any poundage. I've seen plenty of people overbowed at 60# with a compound, or 50# with a trad bow.
On the flip size, if you can draw your bow easily and with consistency, you can shoot enough arrows that you can get a decent session without being tired, you can shoot accurately, and you can do all of that without injury, the poundage doesn't matter.
It is impossible to argue that more poundage is never better, if the above is considered. We all know that more poundage (or a bigger cartridge or whatever) won't make up for poor form or poor shooting. Yes, a fallow deer hit up the guts with my .300WM will be worse off than one hit in the lungs with my .222. We all know that and we shouldn't have to bring up facts like that every time someone wants to ask about heavier bows.
The latest Rogan podcast with Cam Hanes touched on this briefly. I would put money down on the fact that Joe Rogan and Cam Hanes can pull their 90# bows back easier than many people pulling 70#.
Yes, they are outliers. Yes, some people could accuse them of having big egos. Yes, we all know that it's not necessary. But, for me, if you can quite easily, why not?
What most people in the world do with a Ferrari can be done with a Toyota Corolla. Should we tell people who own fancy cars they don't need to do that because their initial cost, maintenance, and servicing are a complete waste of time when you can get the job done with something different?
FWIW I'm shooting 77# at the moment and I can do it fine. I take good care of myself physically, practice regularly and with correct technique, etc. People in my local archery club branch all think shooting 70# is stupid and say things like "well you can shoot it now but you'll end up with broken shoulders and you won't be able to shoot bows ever again."
Firstly, they don't see the merit in shooting 70# for target, but my mates and I all maintain that we want to shoot our hunting bows because our main goal is to be good hunters. Makes sense, right?
Secondly, most of the people telling me I'll hurt myself are clearly overweight, weak, unfit people. I mean no disrespect here, but it's the truth. The way I see some people drawing back 50# compounds, with all bicep, and their elbows far outside the string, means they're destroying their already destroyed shoulders, and no amount of them telling me 70# is stupid is going to change the fact that they don't know what they're talking about.
Also, sorry for the rant. I didn't mean for this post to be that long, and I'm not necessarily advocating for really heavy bows. I'm just making the point that there are always stacks of assumptions made about individuals when this stuff comes up and it's not necessarily warranted.