Yes, those are career numbers. If you take only Klay's "prime" before he got hurt, it's 18.7 pp36 while shooting 41% from three and .560 TS%. With regards to Allen, I would say that his role in Boston was much more similar to MPJ's than his time in Milwaukee or Seattle, so if you just isolate his time in Boston, it's 14.7 pp36 with 39% from three and .574 TS%. His usage was up in his younger years as he was on ball much more often, but otherwise, he was pretty steady across his career.
If you want to compare MPJ with Wallace and Wiggins, I guess that's fine, but I think they failed to live up to their potential for very different reasons than MPJ. Porter is still playing with drop foot in one of his legs because of nerve damage to his three back surgeries. I posted a video a couple weeks back of some of his high school highlights - he wasn't a nuclear athlete like Lebron or something, but he was closer to that second tier of NBA athletes before he got hurt. By all accounts, he is a good teammate that works very hard. He's not a headcase like Wallace or a guy that has completely rested on his talent like Wiggins. He will never be what he was supposed to be before going to Mizzu but that doesn't mean he isn't a good player or has some sort of moral failing to reach that level.