One of the big differences between the old days and today is that you have exponentially more musicians releasing music every day due to how easy it is for bedroom producers to create and release tracks with very little barrier to entry. I can create 10 songs in a weekend on my laptop in my basement and send them out to all of the major streaming services for about 20 bucks.
This floods the market with many, many independent musicians trying to get heard. And the only way to get heard today is to make it onto curated Spotify playlists, build a following, and hope that someone at a record company somewhere hears you and takes interest. Not only is Spotify a tool for consuming music by the public, it is also the main way that musicians have to promote themselves anymore.
As a musician (who gave up the dream of making this a job long ago), it really sucks. There is infinitely more competition out there now, and when you factor in all the AI crap making it on to Spotify (some of which they are responsible for), it is even worse.
What style of music were you making? I suspect, and this goes for more than just the music industry, that it helps if you're a natural self-promoter.
I make 90'S-ish indie rock. I play all the instruments (drums, guitar, bass, keys) and sing.
Having to self-promote is the main struggle, and that's the only way to "make it" anymore. Similar with the book publishing industry. My wife spent a year writing an amazing book, paying an editor, but when shopping it around to publishers, none of them would bite because she didn't already have a social media following. They expect you to have 20k followers knowing that X percent of those will buy the product.
And any time spent self-promoting (especially before launch) is time not spent on the key creation itself. I imagine having a natural interest in it and/or then a very low-touch habit of creating and promoting is important. e.g., set up a camera as part of the writing or recording process, and find a highly-imperfect option for editing the resulting media for upload.
Not GP, but I believe Polyphia [1] self-produces on a laptop in a bedroom (or at least did when they started out?).
1: https://www.youtube.com/watch?v=9_gkpYORQLU