Yeah I get that lol All I can say is that I think some others here have given good advice that balances the reality of the situation being that computer shit is one of the few decent paying jobs, so we're in a privileged position (hence think deeply before throwing that away just now) with passion (capitalism means most people hate their job, very very few are lucky with having unalienated labor).
So as long as it isn't completelt unbearable, it may be good to stay in the field, do what you can to keep on top of skills to do what you got to do to keep the job (and make friends and network and yadda yadda) and put your energy into something more meaningful that isn't work. Organizing, since being a leftist means fighting for revolution is the true goal overall, and even finding some hobbies or projects that get you in touch with the Humanities. Maybe even a place where software and the Social sciences meet. These exist.
If lucky, you may eventually be able to get a job where you use software skills (in high demand, good paying) that is applied closer aligned to something of your interest.
This answer is realistic I think, but it isn't ideal (I don't even like typing it out, and I'm in your boat so I feel the pain), but the ideal situation just is hard to land under capitalism. Maybe it's possible, but it's up to you come up with the plan. Sticking with software but doing the above to save your sanity is one path, and may be the path with less risk. But it requires you to also build up a type of self-confidence and self-knowledge and self-love where you don't judge yourself harshly for not "measuring up" to coworkers who just don't have your passions, interests, and your heart. But that type of self love is good to build anyway. This place will try to rip it out of you if you aren't "productive", but being a dope for capital by spending your energies for its games just shouldn't be the measure of your worth. Even if it feels like it. And I know in my job I get that feeling a lot
I've also converged on the idea that a huge github project is what I need to do too. So I can second this advice (but it hasn't paid off just yet for me, but it's advice I've heard a lot and id rather do this than kaggle exercises or, gulp, live coding interviews)
I know some ML stuff, but I don't know the big data and cloud tools (and im not looking forward to learning them). So I am wondering if I should have a github project using those tools, or focus on ML projects.
Also, I have plenty of my own personal projects that actually interest me, but they are mostly simulations and have no data or commercial application. So I'm wondering if I should quit all that and find some data project that doesn't interest me as much, but employers eat up. And learn all the cloud platforms and big data tools like Spark, etc. Just not looking forward to any of it honestly.
But eh...