Didn't notice this comment before. Yeah, it's tight. It's made to be tight. The thing was made in the 70's. Glance at a few catalogs from that era, that fit was rather in. Very tight crotch and seat, and a weird shape in general. As somebody who wasn't alive then, I can only assume that fashion designers were trying to encourage more sexual openness with that cut. Also, I don't think it's really obvious in those pics, but the trousers also have a slight bellbottom.
It's not something I wear seriously, obviously. At least as a suit. I've been known to break the jacket out as a sportcoat on occasion. If you want someone to blame, Anderson Little made the thing. The guy who runs them now posts here.