IMHO: As someone who thinks blockchains are cool but cryptobros aren't... ideological purity is for extremists and monks. Very few people in the world work for some "perfect" good; we all make tradeoffs moment-to-moment, day-to-day, year-to-year.
Whether you work in crypto or, say, defense or oil or animal testing or AI or finance or just plain ol' Big Tech, your labor output will contribute value to somebody in society (that's why they're paying you), while probably also hurting someone else in society in some small way (luring clueless investors, causing pollution, killing foreigners, exacerbating social conflicts, outcompeting small businesses... whatever). None of us are pure good or evil, and the majority of us live paycheck to paycheck under some corrupt government controlled by ruthless elites, no matter what particular -ism they call it. Your part is unlikely to be more than a cog in somebody else's big, unforgiving wheel.
You choose your battles, do what you can, give back when you can, and try not to cause unnecessary harm, while also taking care of yourself and the people, beings, places, and values you care about. That's already asking a lot of a species barely differentiated from chimps and suddenly given the power of electricity and machines.
As a developer (or some other techie), you have a pretty rare opportunity (in terms of human history, and even most other professions in today's world) of being able to float between verticals with relative ease. Most people can't switch careers without going back to school or going through years of training, but those of us in tech, we can keep mostly our same jobs and skills no matter which industry we choose work in.
So, whatever... self-reflection is a beautiful thing, and the whole point of it is to figure out where you stand relative to your values. Just like you wouldn't blindly follow speculative bubbles, you also don't need to let random online naysayers get to you. They don't get to judge you without knowing your story and situation, and the personal tradeoffs you've had to make in your life.
Consider yourself lucky that you're in a position where you're able to choose. If you decide to stay in crypto a bit longer to see if the technology (and ideology) matures, you can do whatever's in your power to make it less speculative. Write articles as an industry insider to educate people on the differences between exploitative speculation and peer-to-peer decentralized trust networks. Come up with democratic, open-source solutions to distribute the power among individuals, instead of replacing governments with unregulated centralized exchanges that hoard all the tokens, capital, etc. Don't let crypto become the next Wall Street, minus regulation -- and by that mean I mean big investors pooling individual savings and playing dumb games with them for personal gain. Do whatever the opposite of "privatize profits, socialize costs" would be in the crypto world (if such a thing were possible).
Crypto as a speculative financial tool might fail, but crypto the technology is here to stay, just one more chapter in our long book of accumulated human learnings, both good and bad.
If you eventually decide crypto isn't right for you, and you can afford to do so, take a few months off to evaluate your life and your options. Your values don't have to be a static thing, and neither do your passions. Explore both a bit before choosing your next path, and if you can settle on a profession or industry that would make you feel better... great, go for it! You can always reevaluate it again in a few years' time.
Tell your next employer why you entered crypto in the first place and why you left it. Honestly, they probably won't care... unless you switch to the nonprofit space, most employers' primary value is just profit, no matter what the feel-good whitewashing says on their website. And in the event they happen to ask, you'll be able to answer because you've done the self-reflection to be able to answer meaningfully, and you can tell them why you decided to take your skills elsewhere, that it wasn't a light decision, etc., etc.
It's OK to feel lost -- it's not a bad thing, it's an opportunity! Taking risks and learning from them is how we grow as people, right? And learning how to balance your needs against others' is how we strengthen communities, financial or online or otherwise.
Best of luck and enjoy the ride :)