Why endeavor? I recently tried arch for the first time and I've had a really great experience. It runs great on my raspberry pi 5, a device not actually supported by it. It actually feels and works a lot better than the two other distros that do officially support it: RPI OS and Ubuntu.
I don’t think there’s a good reason these days. With ArchInstall, the process is as easy as other distros and then all you have to do is install a DE and you’re all set. Arch used to have a much higher barrier to entry; that just doesn’t exist anymore.
So their reasoning may have been a graphical installer? I also wanted that but since I used a tutorial to get arch installed and working on my raspberry pi, I didn't actually use a graphical installer and I didn't miss it.
Personally I would say start with Arch and if you like it use endeavorOS. Endeavor is just easy install for arch(and the only one I've tried that actually achieved it well) so if you already know the inner workings it saves a lot of tedious install work and has some nice QOL defaults already set like yay colorized