> For instance, `apt install htop` will only ever install the 2.X version of htop in Buster. Including security patches and all, but you won't get a 3.0.0 version without going sideways and add a specific repository for that. Debian will ship with htop version 3 in the next release, but you'll have to upgrade the entire distro for that.

Debian has an official backports repository if you want that behavior. It just gives you the freedom to choose.