I do not know about dwm but many Window Managers, if not the majority, do not have support for Wayland yet or will not support ever. I think Openbox is one of those whom do not feel itself supporting wayland.
The i3wm was forked as Sway what will be the Wayland supported version of it, but I think there is nothing really relevant going in there yet.
For what it's worth, Fedora, one of the few having Wayland as default, will automatically default to xorg if you're not using Gnome I haven't been following that closely, but I did not that when using the Fedora live workstation, (which uses Gnome/Wayland) it automatically scaled the screen on my yoga2, meaning I didn't have to add some .Xdefaults stuff or use xrandr to make the fonts large enough to be readable.
When I last looked, it was just Fedora, and someone's live Rebecca Black distribution--apparently the person was a fan of hers--that defaulted to Wayland, but this was probably over a year ago that I checked. I prefer using openbox and dwm, depending upon the situation, so I haven't checked very deeply into Wayland.