The only way i see it is keep working on tech (safety salary) and do some open source development on the side.

There are so many fields that are so behind in tech, especially embedded devices. Find a field you are interested, say farming, approach people in that field of work and ask them about their needs. Like literally everything is freaking propietary software in every damn field. Then you'd have to rely on some sort of crowdfunding, which is very volatile so thats why you need a job...

I realized the same thing a long time ago (because I'm old, not because I'm a remarkably good person). First I worked in telemarketing and aggressive sales, then when I couldn't do that any more I moved on to mail distribution. Sorting mail by zip code and weight and helping failed deliveries find the right person an so on. I really appreciated how at least me doing my job wasn't actively hurting anyone, but it wasn't really enough. Now I work helping neurodivergent kids pass school. The pay is shit, but wow have I managed to dodge this whole "alienation" thing that is so big in socialist theory. I don't know what your threshold is or what people make in different occupations where you live, but take a look at education. The materially helping people part is there from the start, and whatever education you already do have is likely to at least help. Pay may be an issue, but you should at least look into it.

how material is necessary? You could get more socially useful (though still indirect) work with a minimal skillset change if you go into civic tech. Some city job, or a nonprofit doing data analytics on police crimes or something. I've been daydreaming about becoming a welder or bus driver, or salting for unions at "entry-level" jobs.

Find like minded people and form a co-op

Considering that you already are in the tech environment, have you considered biotechnology/bioinformatics? It's what I'm switching my major to.

Become a machinist and weasel your way into a medical device contract manufacturing shop