Personally I consider lyrics as “just another instrument”. I care more about them sounding nice, and going with the music itself, than caring what it’s actually about.
This
I see lyrics as a tool for crafting the song just like any other instrument. And just like any other instrument it can make or break a song depending on how its used.
It can add a new layer to music if done well or completely disrupt a good melody if done wrong. It also can be central in a song or something added on the side.
A song can use whatever tools it deems necessary to get the job done. That can include lyrics or not. It comes down to the skill and mastery of the artist
As well as what the artist chooses, I also feel that genre has a stake in this as well
There are some genres where lyrics are especially important. Rap is one. Lyrics is the whole point of rap.
There are other genres however that do just fine without lyrics. In Metal, it's often considered not important for your lyrics to be comprehensible. Metal lyrics just needs to sound hardcode and badass, nothing more. Because Metal is more about how bitchin' the music sounds and less about the message. This is why Rammstien is enjoyable even if you don't know German.
Lyrics are even more unimportant in EDM where most tracks don't have them at all, and if they do they only include samples. Because EDM is even less about convenying messages. Instead you listen to EDM to get into the groove and the beat. EDM listeners like myself don't care what the song is about, we just wanna hear something cool. Sometimes lyrics can be a detriment to that and interrupt the the groove you are trying to get to. In those cases, lyrics should only be used if its complimentary to the melody and should never be there for the sake of musical convention.
TL;DR and going back to the question:
Are lyrics really that important? Especially when you listen to music in a language you do not understand?
Ask yourself. Is it a song where you need to know the lyrics in order to appreciate it? Or are the lyrics not the point of the song and it sounds fine even if you don't know the language?
(Or maybe the better question is: which language does it sound better in? original or translated?)