Slow Youtube plugin on 2021-08 (Kodi 19)

This is not super important, but I’m reporting it anyway, maybe it will be useful.
The Youtube plugin is pretty slow when listing pages on 2021-08 on a Vero 4K+.
I tried the same configuration on another Kodi 19 instance (on macOS) but could not reproduce the issue.

Log below is me clicking on Watch Later:
https://paste.osmc.tv/fogoforupu.xml

It takes 13 seconds from the button press to the 200 OK response from Youtube. The HTTP request itself seems to be pretty quick.
There are 6 seconds of nothing happening (line 72 in the log).

What could be the problem?

You should be reporting the problem to the developers of the YouTube add-on. OSMC does not develop or maintain it’s function, features, or performance.

I already reported it in the Youtube plugin thread.
Since it does not happen on other Kodi 19 instances, I thought of posting it here, too.
Maybe it’s caused by some other changes in OSMC.