I never thought about it before but I use upstream and downstream without much though. For my personal devices and containers I use Fedora but when it comes to servers and VMs I use Debian for its stable nature.
I also run Linux mint in my homelab with pcie pass though so it functions like a normal desktop.
I think that is completely normal. I run Arch on my main desktop, OpenSUSE Tumbleweed on my laptop and Debian on any and all servers I host. And I think they all work wonderfully. Even outside of these distros, I can still see the use case for many other distros. I think many popular distros each have a specific goal in mind and they execute it well.