The security risk of X11 is theoretical, not practical. Yes, X11 programs can maliciously keylog each other, but this just isn't a thing that actually happens. And even if you do start installing random malware from the internet like a classic windows user, Wayland isn't going to prevent you from screwing yourself anyway. To actually be safe while installing and running malicious applications you need extensive sandboxing. Wayland can be one part of that sandboxing but is useless without the rest (to prevent the malware from stealing user files including credentials, using LD_PRELOAD hacks or similar to keylog other applications anyway, etc), and no distro suitable for recommending to Windows/MacOS newbs has the rest of the requisite sandboxing. The sandboxing touted by Wayland advocates is very esoteric and without all that sandboxing, a newb using Wayland has to exercise just as much caution when downloading software as if he were using X11.