Those I started, tried out, and abandonned: less than 10
Swedish: I started, did a few units of a coursebook, found out Swedish was just for the rich people (expensive everything, expensive delivery fees, plus geoblocking). If you protect your culture from me so much, not sure I want to hit my head against the wall
And the immersion method "so, I'll just go and read books in the Ikea" would be impossible now
Esperanto: I still respect the community and am happy for others enjoying it. But I was promised a mix of romance and germanic elements, with a few bits of slavic ones. Got a romance language with very few germanic (and even fewer slavic) bits instead and was bored. So, I opted for Italian instead of Esperanto, to be my third romance language.
Arabic: a bit of the writing, a few lessons of Language Transfer. Interesting, but not a priority now. But Maiwenn's log and various other things are tempting! Such as so many patients speaking it, or the more and more present Arabic in the popular culture. And I also get nervous, when people around me speak a language I cannot understand at all (nope, I don't suspect them of being terrorists, I am just a bit too curious person
I feel the same about other distant languages, but Arabic is simply spoken much more around here than Finnish).
Finnish: It was a sort of a bet on this forum years ago. I lost, because I gave up.
Mandarin: a few hours spent on it, fun to explore, I enjoyed playing with the tones, but not too useful for me right now. I have no doubts there are for example tons of books I'd love, or tv series, but that's true about many other languages as well. And even if it is one of the most commonly spoken languages on the planet, I simply happen to meet as many Mandarin natives as the Lithuanian ones. From where I stand, Romanian or Turkish would look like a more rational choice.
Japanese: similar story to Mandarin. I learnt majority of the Kana, did a bit of Lingodeer, but there is nothing driving me to really dive into this language. There are awesome things it could serve me for (but that is true about other languages as well), but the current world makes me not believe I'll ever travel there again, and I have other language priorities.
Polish and Russian: I may return to them and learn them for reading. But right now, they are not a priority.
Hebrew: not sure whether I should count it, I still want to seriously start it!!!