If you learn how an encoder works you can compress the FLAC into whatever format you prefer yourself. I highly recommend 256kbps AAC using Apple's encoder (specifically that encoder, other AAC encoders are much worse) but you can also do VBR MP3 in any bitrate you want. Plus, if you keep the FLACs in archive, you can re-compress them later to a better format if one is developed.
YouTube is absolutely unacceptable quality. The difference is clearly audible even on $5 earbuds. I feel sorry for your ears if you don't hear the difference, but the vast majority of those who care enough to download music will be able to tell the difference.
I personally pay for Deezer HiFi and save the FLACs locally. Friends mostly do the same with Tidal, but both work well for this purpose.
If you want to find FLACs without paying for a service you can check out rutracker. It has torrents for discographies from a lot of famous artists. Alternatively, you could find a stolen account for one of the previously mentioned services, but that goes too far for my morals because you're hurting a normal person with a hacked account.
Hamas combatants were not so long ago normal people, pushed out of their homes by foreign settlers and then have their entire families turned to glass for peacefully protesting. This is not a "both sides have valid arguments" matter.
I'm on Lemmy.ml, so I've been donating €10 monthly for the past year to dessalines!