When I was a kid I had dozens of bookmarks organized by update day

Same. I think it's also because new artists are more likely to publish their work only on big social media sites. And those all enshitify over time and do everything to enclose content in their gated "echo systems". So you need to have accounts on many platforms to even find the comics. Plus, artists face increasing economic pressure and are forced to monetize or drop out of the game.