"reduces fragmentation" wtf lol. If it wasn't for flatpak making it easy to run proprietary / obscure apps on my weirdo little distro (Void Linux, one of the few remaining non-systemd distros) I would have switched to something mainstream like Debian long ago. People are gonna go with the distro that supports (i.e. has non-broken packages for) the apps they use. Having a cross-platform package manager makes it easier for small independent distros to exist and be useful, not harder.
EDIT: And while it's true that Wayland adoption kills obscure X11 window managers, Wayland adoption also spawns a wide range of obscure Wayland compositors. Think hyprland, wayfire... It's by far not all Gnome and KDE! If anything, we can expect more people making Wayland compositors as hobby projects, if Waylands claims about a simpler codebase are to be believed.
In conclusion: this is a stupid argument lmao