I believe this is the third request for Alpine. This time, though, development has resumed. The last release was in October of 2020. The project seems to exist again. Website, as before, is http://alpine.x10host.com/.
As far as what it brings to the table, well, it's a CLI email client. That hasn't changed since the last couple times, and it still looks useful.
It is definitely open source. Here's the tarball: http://alpine.x10host.com/alpine/release/src/alpine-2.24.tar.xz
I also volunteer to package and maintain it. You'll know me as sheepman in IRC- I've been around for a while.
Thanks for your consideration!