I feel like I could make an argument for both sides, and I genuinely don't know what the general consensus is here.

On one hand, it's intentionally put into the game and the developers expect their players to slide.

On the hand, it's very easily exploitable in a way that I feel the developers didn't intend.

Would like to know so I can start using this in glitchless runs, if it isn't considered a glitch that is.

Good ​question, I would categorize it as a feature, which can be exploited. Not a glitch imo, though.

Still I think it should be allowed in glitchless runs because it will be hella hard to tell if it's being exploited or just used, because it can be done everywhere even with a small tap in the C key.

pretty sure its just the natural physics of the Unreal Engine. def a feature. and anybody can simply slide down a hill.