When you say it looks easy for people to rip Uke apart, it may be because they altered the dismemberment threshold setting. That setting controls how easy or difficult it is for joints to be torn off / dismembered.

Mods like the online TwinSword4 have a low dm threshold (around 50), which is why you can separate limbs so easy. Mods like Aikido where you aren't supposed to dismember your enemy have a very high dm threshold setting (like, 375).