What i described was about Wayland, GNOME and Gtk specifically, not the entire "Wayland world". Wayland has been a mess that could have been completely avoided if people just tried to fix any issues with Xorg instead of falsely claiming that Xorg cannot be fixed and we'd had proper support for HiDPI, HDR, mixed refresh rate configurations with compositing and all sorts of other nice things at least a decade ago instead of creating a pointless schism in the already tiny Linux desktop ecosystem but ultimately you cannot control what other people spend their time on.
1) Window Maker does not provide anything to any application, if applications need such information they have to use the extension APIs themselves. IF there was an agreed upon protocol for window managers notifying applications to scale themselves, then Window Maker could implement it. But such a protocol does not exist.
2) Window managers do not provide any information there at all since there is no such support. And yes, all Wayland compositors do need to implement that stuff, but because it started from a clean slate and Wayland compositors had to be written from scratch anyway, it was easier to convince developers to do that because they self-selected to go through the effort of making a Wayland compositor in the first place. As i wrote in my original post, the issue here isn't if something would be written or not, but convincing the people who work on the projects. It is mainly a social issue, not a technical one.
3) Yes, without any other support in place, GUI toolkits and other applications can use the information exposed RandR to implement scaling themselves but, as i already wrote, this is a fallback solution because the rest of what i describe is not there. This is far from having robust support, ignores things like custom scaling options, handling moving windows between desktops and support for applications that do not do scaling themselves (which is many of them), among other things.
All of the above are things i already addressed in my original message BTW and again, the issue is not technical but social/political. It is about convincing people to cooperate, not if something is technically possible (and let's be honest, it isn't like Xorg's code is written in stone, if something is currently impossible, the code could be extended to make it possible).
What i described was about Wayland, GNOME and Gtk specifically, not the entire "Wayland world". Wayland has been a mess that could have been completely avoided if people just tried to fix any issues with Xorg instead of falsely claiming that Xorg cannot be fixed and we'd had proper support for HiDPI, HDR, mixed refresh rate configurations with compositing and all sorts of other nice things at least a decade ago instead of creating a pointless schism in the already tiny Linux desktop ecosystem but ultimately you cannot control what other people spend their time on.
1) Window Maker does not provide anything to any application, if applications need such information they have to use the extension APIs themselves. IF there was an agreed upon protocol for window managers notifying applications to scale themselves, then Window Maker could implement it. But such a protocol does not exist.
2) Window managers do not provide any information there at all since there is no such support. And yes, all Wayland compositors do need to implement that stuff, but because it started from a clean slate and Wayland compositors had to be written from scratch anyway, it was easier to convince developers to do that because they self-selected to go through the effort of making a Wayland compositor in the first place. As i wrote in my original post, the issue here isn't if something would be written or not, but convincing the people who work on the projects. It is mainly a social issue, not a technical one.
3) Yes, without any other support in place, GUI toolkits and other applications can use the information exposed RandR to implement scaling themselves but, as i already wrote, this is a fallback solution because the rest of what i describe is not there. This is far from having robust support, ignores things like custom scaling options, handling moving windows between desktops and support for applications that do not do scaling themselves (which is many of them), among other things.
All of the above are things i already addressed in my original message BTW and again, the issue is not technical but social/political. It is about convincing people to cooperate, not if something is technically possible (and let's be honest, it isn't like Xorg's code is written in stone, if something is currently impossible, the code could be extended to make it possible).