I'll be honest, from a bodybuilding standpoint, Robin's physique is terrible. He looks like shit, it's a pity but he just didn't handle things well, gained mass in a way that absolutely did not suit him. He could've easily gone for a classic physique type look, but I guess it wasn't a big thing back when he was starting out, so he just tried to go for Mr Olympia Open size and his body simply didn't respond well
As for Connor, I disagree. Not every guy has an endless capacity to gain muscle and look good. Connor has a big frame but otherwise the typical tall guy limitation on putting size. Back in the day the steroids gave him really bad acne, and probably several other side effects we never heard about. He's surely happier like this. I do agree with you that him getting to insanely big levels and getting muscle worshiped and dominating others at that size would be smoking hot... but reality is more complicated
You have guys like Laszlo Kiraly, Ramon Dino, or Chris Bumstead... they're genetic freaks. They pack on TONS of lean muscle mass and end up looking like an anime character. But they're 1 in a million, most guys end up looking like Robin Strand