I saw someone talking about this online recently and I wanted to bring the discussion here too.
Libraries can be supported by a number of means including website traffic, social media likes, newsletter sign-ups, visiting events/ programs, and, of course, checking out books.
I have had a long history with my local library and it blows my mind, sometimes, the services they offer that people don't know about.
When I was a kid, I largely got into reading because of a monthly book club our library ran. Before that, I had never enjoyed reading books outside of a select few series because I wasn't encountering books that spoke to me; but the librarian that ran the program was very savvy and picked great books that children could enjoy. To this day, I am still grateful for that program.
They also have programs aimed at adults that can range anywhere from book clubs to classes, and even very interesting author talks from time to time.
You can also borrow all sorts of exciting media aside from books. You can rent movies/ TV shows, music, and even video games these days. This is really fantastic for movies/ games that you think you'll only want to enjoy once or twice and don't need to own. It's also worth noting that your library can have some pretty rare media that can be hard to find online or in stores.
Additionally, your library can sometimes have large niche equipment on hand for you to use too. I've seen some libraries with 3D printers and some with projectors you can borrow. A lot of time you only need to use these large appliances once or twice a year. In cases like this, it is much better to borrow from your local library.
Finally, your local library can just be a fantastic third space. When I was a kid, the library was a great place to meet up to work on class projects, not just because they had lots of information on hand and a Wi-Fi connection; but because they had all sorts of places you could set up and work. There were conference rooms, tables, benches, and even armchairs for reading (though those weren't very useful for group projects).
If you haven't visited your library recently, I highly recommend checking it out. It may have more to offer than you remember.
If you are interested, I have also included the original skeet that inspired me to make this post here.
I understand your sentiment, and I've certainly gone to the library far less since becoming far more comfortable with the Internet.
Having said that, the Internet is a dangerous place to people who don't know what they're doing. Think about how many people don't even use ad-blockers; and that is a bare-minimum from a safety perspective.
With that in mind, the library is a powerful resource to people who can't navigate the shadier parts of the Internet.
It's also worth noting some people have atrocious Internet speeds. For people with slow Internet, it could take an unfathomably long time to download/ stream something versus instantly being able to watch/ read/ play it as soon as you get home
Plus, as I said, it offers more than just books and TV/ movies. You can borrow equipment, have a place to work, have someone knowledgeable point you in the right direction. These are valuable services offered that I don't think the Internet will ever be able to truly replace, and that's not even getting into the value of building up your local community.