The core benefit to me of FLAC is that it's lossless. I can convert the same file to an MP3 for the car and OPUS on my phone and don't have to worry about (compounding) losses in quality.

I stream FLAC at home because I already have it there but I can't say it's "better" than 320 MP3s.

I did a re-rip project during Covid because so many of my rips were 128 bit MP3 from back when storage costs drove all CD ripping decisions.

Edit:typos