I believe that, (possibly only) in the early days, it offered to add any imported music to your library, which I think it indeed did by converting to AAC and putting in a directory structure of its choosing.

It probably could convert to AAC, but the biggest issue for collector nerds with carefully curated collections of mp3's organized in folders by artist and album and with perfect metadata was that iTunes would take all your hard work, shake it around, rename all the files and dump them in a single folder and fuck up your metadata. At least that's how I remember it, but it's over 20 years ago ...

I think the core lesson of the story is knowing if your hobby is listening to music or curating a music collection. Optimize for one or the other.

I went from meticulously curated MP3 collection on Linux to letting iTunes do it for me, and I realized that the meticulous curation and hunting down album art and everything was a hobby I didn't actually love. But if you do love it, great! Different tools for different jobs.

iTunes is trash on both of the jobs you mentioned though. Still waiting for a worthy alternative to foobar2000 on either Mac or Linux...

But foobar2000 already has an osx version (https://www.foobar2000.org/mac), I've been using it for years.

Submitting to iTunes made syncing to the phone much easier, but I've been using claude to rebuild/repair my 20+ year old library, and have learned that iTunes has very weak if any support for "work" - a feature it has to split up classical music the way the CD does (once file per movement). Frustrating that there will likely never be a high-quality syncing player that works well with iPhones.

I remember the trick was to use a network hard disk or drive for the music. iTunes kept the organized folders and all files untouched while building its metadata-only archive in local. But in general, yes, the tendency to mess with your file was built-in.

The trick was to skip the onboarding and go into the Preferences, there was an option there to disable putting your files in the music library folder and messing with the layout

edit: I just compared iTunes 4 and Music in Tahoe and they still have the same preference! It's funny how they clearly did a s/iTunes/Music/, resulting in the "Music/Music" dir https://kalleboo.com/linked/itunes4-vs-musictahoe.png

As I recall it, the AAC option was for syncing to iPods with lower capacity (like the Shuffle) so that it would convert your 320/256kbps MP3s to 128kbps AACs to fit more music. It did this for a copy of them though, I've never heard of it actually converting your main library and checking out an old version of iTunes it has no way of converting your whole library (just individual tracks one by one).

Having iTunes organize your music into its own folder structure was an preference you could turn off, but that option was not shown in the onboarding so it ruined many a people's meticulously organized files...