At this point, being on this planet is a losing cause.
I strongly disagree that unpopular things are automatically a losing cause though. I use and do some unpopular things because it’s more ethical or more beneficial overall, but I’m not at all troubled with it. I just try to be a somewhat decent citizen where many others would just be like “lol I don’t care about any consequences, just give me the cheapest or most convenient option”. I’m not like that. And I think more people shouldn’t be. But, again, at this point… it’s definitely a losing battle. But I still do it because then I can tell myself that I at least tried to do the somewhat right thing. It’s kind of just to have a clean conscience, whereas some others are completely fine burning the world for their own short-term gain. That’s basically the difference.
Linux phones are usable right now, but of course you have some limitations in practice… many apps aren’t available or you have to use workarounds. If you mostly use open source applications you could be fine though. Although it’s likely that you still need a secondary, small Android-based phone that you turn on just for those rare cases where you absolutely need a certain mobile app and it’s only available for Android. At least while Linux mobile OS usage is still low. It’s probably going to grow faster in the future, because those monopolistic companies usually enshittify their products and services at some point (Google is already well on it) and then regular Android/iOS users become so annoyed at what they’re using that they also open up more for alternatives. It’s basically what’s happening in the desktop OS space right now - Windows continues to become more user-hostile and annoying to use, and desktop Linux passively (as well as actively) becomes more popular as a result. At some point, these companies forget what made their products popular in the first place and are only operating in the mode of milking users for data and profits, because they don’t need to work hard anymore to improve the product - it’s already popular enough. At that point, regular users who normally don’t care about things like freedoms, privacy and ethics in the product they use will notice that things became worse and might switch simply because of inconveniences they didn’t have before.
Another very good option beside Linux-based mobile OS these days is GrapheneOS. It’s the best Android-based distribution you can have currently, nothing comes close (not going to elaborate here because long post is already long). But you still should be prepared for increasing hostility from Google towards unofficial Android distributions, and some apps which use the Play Integrity DRM to not work. If you encounter this, make sure to let the app developer(s) know. They need to realize that they are only serving Google’s interests with this, not their own.