You agreed wholeheartedly with a post that was sneering at people who are interested in interior design - as if that means they can't be interested in anything else - and you literally said very clearly that people who don't read for pleasure must have enormous amounts of empty time, as if you imagine there isn't anything else worth doing. You even admitted that it would be an 'unpopular opinion' so I'd have thought you had a good idea of what you were implying.
But I'll take your disclaimer in good faith and proceed on that basis.
I'm still rather unclear as to what 'quiet things' are. I don't think popular culture is any less quiet than anything else, is it?
Maybe you need to think a bit more openly, rather than trying to categorise things quite as rigidly as you do, if you really do want to find people you have more common ground with.
For example, you say you aren't interested in 'popular culture' but you mention, for instance, that you 'watch a lot of Walter Presents'. That is popular culture :) It's TV drama. The fact that it's not in English doesn't mean it's not popular culture.
Similarly 'travel' - you might not like to travel, but a lot of people who do will have had all sorts of experiences that are likely relevant to things you do like. History and culture are often the main motive for travelling - certainly for me.
Same with sport, actually - obviously people banging on about the intricacies of football tactics is dull to anyone who doesn't like football (or any sport; I'm just using football as an example) but there's an awful lot about football across the world that has fascinating historic, cultural and political connections.
If you're of the mindset that 'travel, sport and popular culture' are essentially 'package holidays to Tenerife, Match of the Day and Celebrity Love Island', that's probably not helping matters when it comes to connecting with people.
For what it's worth, my partner and I both have some very niche interests and we're both very introverted and value solitude. I do get what it's like to have interests that people around you don't share. But it doesn't have to isolate you if you think a bit more flexibly, and curiously, about things.
You also mention that other people might find you intense. By that, do you mean that you tend to fixate on the things you're interested in and want make them the sole focus of your conversation? Because that seems more about personality type than the interests themselves.