I think it depends on how you enter, Liftoff and Connect do

I will check qos, i think i saw it enabled or something, thanks

My isp gives me something a public ip like 200.191.57.xxx, but that ip changes and I can't open any port. Then my isp's router's local network is 192.168.0.xxx, my TP link router connects there (to 192.168.0.3 i think). Then my TP link manages ips 192.168.1.xxx. My jelly server is at 192.168.1.10, my devices are at 192.168.1.5, 8, etc.

Everything is local, nothing goes outside

You can try LibreTube, it has almost all the features of youtube. Only downside is some videos are slow to load, but if you can host your own Piped instance that's solved. It has sponsorblock built in, regular updates, and a better ui imo

From my internal IP (192.168.1.xx), I don't access it from the outside (can't open ports on residential connection in my country :c )

All my devices are connected to my own router, then that router connects to my isp router, which then connects to the internet, so its very weird.

The only thing I configured was reserving an ip address for my server on my router, but I don't think that should influence...

Libretube with my own Piped instance, almost flamless. One line setup with docker, Runs perfectly on a 5$ VPS. I haven't entered youtube in months, there is no reason other that to import suscriptions, channels, etc.

Only problem is for some reason some not-so-popular videos are slow to load on 720p, but load fine in 480p or 1080p. Really weird.

A year ago that would randomly appear for me. It seems they were a/b testing it.

Ah, asprite, an example of the reason why people pay for binaries, and open source is economically viable. Took me so long time to install and setup all the dependencies, by the time it was installed i got bored.