If you're willing to check out self-hosting, Navidrome is fast, slick, and under active development. It provides a Spotify-like experience from your local collection and is compatible with dozens of clients for different platforms.
I'm using DSub on my android phone to get a nice mobile player, which also sync's tracks locally to the phone if I wander into an area with low or no signal. Navidrome being compatible with the Subsonic API means there are several players on all platforms that can hook into it.
I drive through areas with no service for a few hours per week.