Absolutely worth checking into IMO. If your e-reader device does support library connections, so much the better, but if not, your phone/tablet will.

In addition to e-books, your library also likely offers access to other services including streaming. I have access to Kanopy, which has an interesting catalog of movies and shows that is well outside the mainstream. I've found some interesting stuff on there to consume even though I don't use it as often as Netflix/Apple/etc.

Regarding Libby and the Palace Project, I used Libby for some time but shifted to Palace after reading (here, here) about the e-book lending market space and how ripe for enshittification it is at present. (Overdrive, the company behind the app of the same name and the Libby app, was recently sold to private equity firm K.K.R., notorious for horrible business practices. Overdrive controls about 90% of the library lending market, so I'm a little fearful for what might come.) The Palace Project is a non-profit, so I'm supporting it as a competing platform in case Overdrive starts to tank. The Libby app is more polished, but the search, borrowing and reading experience on Palace is largely comparable and still just fine.