It's been a long time since I've really taken a shot at it (late 00's, early 2010's).
My biggest obstacles:
1) Meeting a lot of people, EHarmony being the primary example, where I respected them but my attraction level was maybe 50%. That brings up two problems - first that if I'm not attracted enough there isn't really a good basis to start with, second it's really a blush and I feel awful when I'm the one whose pulling away - it happened often and for anyone whose done the rejecting trust me it's miserable (especially when it's someone you intellectually and socially respect - you feel like less of a POS being rejected).
2) There's a really sharp looks / ego gradient where you can easily feel feel like most people you'd be attracted to can just about point a gun at the ground at your feet and tell you dance. What really sucked - those rare one or two times where I met someone who I found attractive and they found me attractive (both physically and intellectually / creatively) there was a hard mismatch, most notable case where I was living in a relative party house and she was in Alcoholics Anonymous.
It seems like the statistical odds of finding a proper match are just miserable. Lowering your standards doesn't work because I can about as easily do that as jump off a cliff (and this is where when I hear about women who've gotten masters degrees or more, making 100K+ not being able to find a guy I really don't think it's all in their heads - I'd imagine its how I experience things). It's one of those cases where breaking certain boundaries like taking up someone's time for attention that you're not attracted to feels morally wrong, making a move even worse, and even worse still - as mentioned earlier - when you have a lot of respect for who they are as a person.
I remember listening to Stephen J Shaw on Chris Williamson's channel where he was talking about the dating and mating demographic crisis and he mentioned that 80% of both men and women who were single actually wanted to be married with children but couldn't find the right person or just had too many interferences with life. When there's no steady physical world places to meet people, where the social sphere has virtualized online as well as the move to dating apps, and then the workplace is ruled out as an inappropriate place to meet someone - that really shrinks everyone's options.
The other part - I'm living at home with my parents so I don't feel right with that part as well. Making okay-ish money (> 40K, < 50K) but it's really not enough to progress, other than that I'm investing a lot right now, figuring out how that goes, and so far with the test cases I've worked with so far it's going pretty well, I just have to hope that I catch better breaks on my finances and income or can really build a good war chest with my investing (I work from home so I can both program and swing-trade).
_________________
The loneliest part of life: it's not just that no one is on your cloud, few can even see your cloud.