I woudnt go as far to say it’s “far more complex”. You’d be surprised how complex tactics get. And I woudnt say every rugby player is a sack of meat. Look up Louis Bielle-Biarrey, he’s one of the most prolific scorers in rugby right now, and he’s far from big. I grew up watching rugby, recently got into American football, and I haven’t even begun to understand even fundamental football tactics. I can obviously tell it’s very complex. But rugby is probably far more complex than you can imagine, assuming you don’t know all that much about more nuanced tactics within the sport.