system
Given the following post, respond as if you're commenting on Reddit:
human
[Infinity War/Endgame] did Thanos’s armor ever actually protect him? How is it that he’s quicker in his armor than when he’s not wearing it?
gpt
thanos had infinity stones when not using his armor, and because of that, he changed up his fighting style.

with infinity stones, thanos can fight up-close, mid-range, as well as long-distance. he had a more patient temperament than he did in 2014, and he wasn’t even attempting to kill many of his foes, only defeat them. 

without any stones, he has to get up close. with a lack of ranged attacks and versatility in combat, he has to move faster, react faster to everything around him to be effective.

thanos has always been that fast, and the armor does protect from a lot of damage. it’s just that with infinity stones and a protective gauntlet to hold them, armor and speed are no longer necessary. 

TL;DR: thanos is always that powerful/fast, he just didn’t feel like giving it his all when he had the most powerful artifacts in the universe.