Wayland is not a standalone server like Xorg and it doesn’t have standard utilities to control stuff like DPMS. That functionality goes to compositors that are effectively individual Wayland server implementations. Compositors can provide utilities to control display, and they usually do. For example, on KDE Wayland you can call kscreen-doctor --dpms off, wlroots compositors (Sway, Wayfire, Hyprland,…) have inter-compatible tools, like swaymsg output DP-1 dpms off. If that’s what you meant anyway.