You're reading too much into it. GTK+3.x has supported Wayland for various versions already. Fully supporting everything required changes (additions) to Wayland (the spec). There's still a few things missing in Wayland for GTK+ to support everything. Qt support, we're (=GNOME) not the ones to know.
Aside from that, this bit is probably about if we set environment variables to prefer/force Wayland backend, or leave it up to toolkits to discover. For GNOME to change behaviour of Qt might not be a good idea (or maybe it is :-P). As such, "maybe".
Aside from that, this bit is probably about if we set environment variables to prefer/force Wayland backend, or leave it up to toolkits to discover. For GNOME to change behaviour of Qt might not be a good idea (or maybe it is :-P). As such, "maybe".