body animation still doesn't work

This gives me no information or context. Attach videos or screenshots.

I've already done it and nothing has changed, except that the glider has become much less likely to get stuck in the folded state, the character also seems to be standing and not even raising his hands

I see - do you have other animation based mods installed?

This might not be the same cause for the issue you are having; but, when I saw this I decided to see
if Lunade-FastAnim might also cause this (it does) as I have had issues with FastAnim breaking animations for other mods. If you have FastAnim installed consider trying to remove it to see if it is the only cause of your issue.

I see - do you have other animation based mods installed?

player-animation-lib-fabric

Do you need that for other mods you have installed?

for two already installed (on which some others depend) and two more are planned for installation

better combat, Combat Roll, Emotecraft, Kelvin's Better Player Animations

the same issue is also occuring for me

Will be solved when we move to Player Animation Lib