I usually go via new pipe but at work I don't know what I'll do, since I suspect yt mirrors will be blocked

There might less known instances or test servers. Startpage search's anonymous view which connects to a proxy usually worked but I suspect youtube might block it on some ocassions with bot accusations.

What if they start dubbing the lyrics in songs?Is it smart enough to at least to not do that?

There might be userdefined tags that help identify it as music and the copyright thing does catch songs by the name so probably but If it is a song mixed with other audio in it then it might fail or it might autodub despite being capable enough to avoid doing it because google said so. I think I saw a section with dubbed voice mumbling something (not even the original speech artifact that appears often) in a section for a few seconds where there wasn't actually any dialogue. It took a lot of liberties with the translation so a lot of those snarky comments were either omitted or left feeling mild and it doesn't resemble the tone that was used in the video, instead it sounds flat and without emotion. The music in the background had artificats or was sometimes missing, the audio would speed up or slow down constantly. The original audio only used a well known voiceroid and some basic texttospeech voices so I wonder how bad it would be on a video with normal speech.