To ask when you removed baby gates?

[PatrickTheStarfish]

I have a 2 year old and a 4 year old.
Pressure fit gates at the top and bottom of the stairs and kitchen doorway.
I rent so have to use pressure fit, can’t be drilling holes everywhere.

What age is best to remove the gates?
Four year old has just accidentally pulled the bottom gate off bottom of the stairs whilst getting to the toilet (he knows how to open it)

Obviously I’m worried about the four year old hurting himself doing this but equally worried that the 2 year old will start messing around on the stairs and fall down.

We still have one at the top of the stairs. I won’t take it down after a friend of mine’s 3 year old toppled down the stairs getting up in the middle of the night. We only put it on at night though.