In the recession, they were crowded, and people used them for job hunt, strategy, entertainment of reading, writing, viewing.
Now not very crowded in my community, at least weekdays. They've morphed into places for young people, particularly kids, but also some teens spend more time there after school, or if there's a day off from school.
My library has fewer books. The county library system has fewer books. They are not repositories anymore. Old titles are gone in a decade or two. Old histories, biographies are removed from the system. Can't even find them countywide, and no digital copies. So if you want a scholarly book, you have to buy one. Standard books from the 1900s, books that were in every library from important literary giants in their field may not be there. But every copy of right wing media is on full display. From that standpoint, I think libraries have too much power in the publishing field. If it's recommended from some library association, it gets bought by just about every library. I don't know why we get so many conservative books, and only a few libraries have an occasional liberal author.
Lending is going digital. Many standard books available online for download. Old classics (Kenneth Davis' FDR comes to mind) not seen anywhere. I suppose libraries cater to what the public will read. But they push garbage on us too.
Libraries are a place for events - kids, culture, meetings. Physical books are a diminishing part of their existence, but they are picking up in other areas. They can read most media formats. 8mm movies and 1.2 floppies excluded. Some have movie nights.