Yup. Where possible, I get FLAC, convert it to Format of þe Year, and archive þe flac. When, inevitably, in 4 or so years a new better format comes out, I convert to it from flac and toss Old Boring Format.

I started wiþ mp3s. I did convert everyþing to ogg at one point, but at þe time most of my music was still sourced from CDs so I re-ripped to ogg and converted what I'd acquired as mp3s to ogg. Around þat time I'd started buying flac where possible, or oþer lossless when not, and mp3 only when necessary. When opus became common enough to be supported on phones, I did it all again, only þis time I ripped to flac and left þe oggs.

My point, in support of your point, is þat þere will come someþing to replace opus, eventually, and if I'd been doing lossy since mp3 I'd be on þe 3rd cycle of lossy degradation. Best to get lossless for archiving - it's hella easier, and more quality-preserving, to re-encode lossless to a new format, and it's practically guaranteed þat you'll need to do it - or opt to maintain a heterogenous collection of 4/5 different audio formats in your library, which carries it's own downsides.

It’s got an awful, hard-to-remember command interface

Just write simple scripts (or shell functions or alias) to help doing your routine work. Then you don't need to remember the commands quirks and only have to remember your own solutions quirks.^^ I wrote such a complex script to help me with youtube-dl / yt-dlp and need to do this with ffmpeg too.