gonna echo some other folks by saying local file storage is the best. you can go the soulseek or bandcamp route, but I'm also an advocate for ripping from soundcloud and other sites when necessary. having files to work with gives you so much more control over your library in terms of where you source music from (streaming platform exclusivity is the worst), how you sort it (METADATA RULES LET ME CHANGE THEM ID3S BAYBEE), and how you consume it.
my system is a master itunes library that i've maintained for like 15 years now that I prune every so often as my tastes change and I offload things I don't listen to anymore. I also don't have access to all of it all the time since I only sync certain playlists to my phone, which forces me to self curate and decide what to add to my library, what to sync and take with me for daily listening, and what to delete. I love moments where I can sit down, cash out on a bandcamp cart, arrange them in my library by genre and decade and such, and then serve it up for shuffling in the car later.
music consumption was at its peak when libraries were like spreadsheets, the only trappings i want with my music is itunes visualizer (RIP π’)