People do still talk about programming online, just not on Stackoverflow.

I think since AI finally provided a non-adversarial alternative to Stackoverflow it lost the critical mass to be a one stop shop for all tools/languages/projects. So people just reverted to communication forums specific to those tools/languages/projects.

There are plenty of project mailing lists, GitHub issues, language forums, blog posts etc. that are still active. E.g. just the Rust users forum gets more than 2-3 posts per day.