Those are a lot of libraries to maintain. I initially had local music on PC and then with move to Mac, stayed with iTunes for a number of years. As soon as my library started to get too big to fit on my local desktops or laptops, I knew the time for iTunes was over. Since then, it's been all music on external drive with the same structure and accessing them through different software over time such as Clementine, Amarra, Audirvana Plus, and now Roon along with Bryston.
With respect to the other older and personalized music that was on playlists in iTunes and such, over time I've been manually matching it with Spotify. I know it's lossy, but it's intuitive to use for the entire family and I can actually find odd music here and there that other services simply do not have. I'm only interested in lossless streaming if Spotify does it. No interest in Amazon, Qobuz, or Tidal lossless. I don't need hi-res either. All my music is 16 bit along with certain 24 bit that are more linked to audiophile labels or special releases. Otherwise standard CD quality (16/44.1) lossless is all I need.
I gave up on DAPs, external DAC/amps or transferring music to phone. I can recreate the same music on Spotify and their playlists and simply save them for Offline playback whenever travelling.
Local music is now only reserved for home. Spotify is used exclusively when outside or if there are parties. Everyone knows how to use Spotify that comes over or family members. Roon and Bryston for my personal use.