billd91
Not your screen monkey (he/him) 🇺🇦🇵🇸🏳️⚧️
I'm not so sure. Lucky shots or attacks that go amazingly well to plan, matching the attacker's intention better than might have been expected, are certainly one thing "critical hits" model. But it's clear that there are other cases where they model other circumstances besides this (I look at RoleMaster's and DragonQuest's critical hit tables to see proof). I think I could make a case for 4e's "critical hit" to be "just" an attack that goes very well to plan - the damage caused is only above the maximum that could theoretically be caused by a "non-critical" attack by virtue of enchantment effects. 3.x's damage multipliers, on the other hand - differentiated by weapon, to boot - seem to be trying to reflect something more.
You are looking for a difference that isn't there. Critical hits in 3e and 4e play the exact same role. What's different is 3e tried to provide different behavior profiles for different weapons - somewhat more common vs less common but doing more damage (both of which even out in the long run) - so that the different weapons chosen actually mean something in play. That's pretty much it.
If you look at the damage most x2 weapons do, it's even comparable to a 4e's crit. 4e does max, 3e x2 weapons get rolled damage twice which tends to average out to very close to the max damage for the weapon. So the difference you're seeing in role is, I believe, manufactured by you.