Why is Libretube so fucking slow?

Watching videos has basically become impossible. Not even at 144p, not even just the audio loads more than 20 seconds and then stops every 2-3 seconds. I'm really not sure what causes it.
Am I using the wrong instance?
Is Google interfering?
Is my phone or the app not working correctly?
Is my ISP messing with me?

Any tips would be much appreciated

edit: Might have overreacted there a bit. Videos load and run fine in my mobile browser on any network so I doubt it's the instance nor my ISP.

Still leave Google or the app as possible reasons. 🤔