I can’t speak to the corps boot camp, that’s a different animal obviously since once you’ve done it it’s transferable anywhere. But when I did basic it wasn’t hard at all I got the physical fitness badge and scored in the 90’s (back then you could get over 100 but I think I’ve changed the scoring and test in the almost 20 years since)
For reference I was probably 2 years out of college and out of shape and still drinking with friends every weekend(and some weekdays) and not exercising regularly. Then I spent about six weeks before hand just running every day doing push-ups and starving myself(not the ideal plan but I was like 23 and stupid) that was enough for me to drop from 250+ to a weird skinny fat 230’s. I’ll attach pics that borderline alcoholic who did a few weeks of training was at the top of his class fitness wise. My younger cousin went in right after college a few years ago and he said in regular boot and when he to ranger school they are trying to push more lifting. It was just the 2/2/2 when I was there that was the full focus.
I know this about marine boot camp I watched full metal jacket with my dad as a kid and I don’t think I’ve ever seen anyone hate a movie more. He was a an m-60 machine gunner marine in Vietnam and called the first half (the greatest comedy he’s ever seen) said boot camp was about 10,000 times tougher then the “tough” bootcamp in the movie and among his many complaints (the way the guy wears his ammunition in a bandolier) “you’d never do that it would get filthy” was how he repeatedly said they’d send private pile to fat boy camp and not keep him.