Nah. Rucks, mauls, binding, timing for lineout and tackles, scrums, different types of tackles, fends, running off the ball, passing off both hands, and all the options to consider. The technical training to scrum properly is huge.
Compare cricket training - nets and fielding practice (easy but stressful when getting bounced), practising football - fine skills and lots of running but repeated skills (headers, timing corners, improving weaker foot, and tennis is hitting a lot of balls, running hard, and developing a gun serve. Rugby training is super complex - the 2021 rugby union law book is 156 pages long (I just checked) and unless you're Richie McCaw or a gun referee very hard to prepare for and play at an elite level.
I've played all of them to a bad standard (rugby, cricket, tennis, football) and rugby's the hardest and most technical especially forward play. Playing in the backs is a lot easier which is why league backs can switch to union. Brad Thorn is a league forward who switched and (despite being an amazing pro with a crazy work ethic) still took a few years to understand what to do.