Because Xbox comes from Microsoft and the PS5 does not. You are able to play "PC only" Games like Microsoft Flight Simulator on Xbox but not on Playstation. And thats why you have mouse support only on Xbox
since the PS5 version is available from a relatively short period maybe they still have to implement the mouse function.
I believe it's for the same reason mouse functionality is broken in Minecraft PS4. The Xbox comes with mouse support by default, as it is needed to use Universal Platform apps that haven't been optimised for controllers. The PS4 has nothing like it from what I've seen, which is why the mouse in Minecraft PS4 is completely broken and a pain to use. It's too much effort for DTG to add. I expect mouse support to never be added to the PlayStation versions of the game.
The PS4 and I would presume the PS5 do support the use of a mouse, you can plug one in and move around the menu. It's just that very few games fully make use of that ability. There's only about 7 as I could find that list mouse support, mainly shooters. Some games use mouse movement as a simulated controller input which isn't ideal (perhaps Minecraft is like that Doomotron?). So it theory TSW could make use of one on both PlayStations. It'd make a nice addition at some point.
No, it works like a mouse but the mouse is completely broken. Moving the camera in-game moves it in menus, so when you open the inventory for example, the cursor will be miles from where you left it. I don't know if it's been fixed since I haven't played Minecraft for about a year now, but since the Bedrock edition is a complete mess of a game I doubt it.
I do not believe the mouse functionality is exclusive as games like cities: skylines have full keyboard and mouse support on both PS4 and PS5 as well as having controller support too…
It was a silly post that doesn't make any sense. Quite frankly, the only possible reasons for there not being mouse support in TSW are that the PS4 doesn't have built-in mouse support and DTG are too lazy to add it themselves, or it is built in but DTG can't be bothered to make it work. Minecraft, Cities Skylines, The Sims 4 and even Gran Turismo Sport have mouse support, so it's hardly like DTG can't add it if they tried.