It is, though. Unity doesn’t define the cursor at game start. It compiles it into an asset during build. So when it’s published, that’s it.
They can, and obviously have, changed the default cursor. LE’s cursor is obviously one they made and isn’t the default one. But once they build the game so they can release the new patch, the cursor gets locked in and can’t change anymore. To change it, they would need to make the changes to the cursor and then build it again and release once more.
There is no way in Unity where you can have one cursor style and I can have another cursor style. Once it’s in, it’s locked and it’s the same for everyone.
What Yolomouse does is a hack. They detect the mouse render and superimpose their own renders on it. It’s the same thing EHG would have to do to accomplish this. They would need to create an external tool for it.
And yes, it would likely take months, even copying their code. Which, again, would be a totally futile thing to do when you already have software that does exactly that.
At least the Yolomouse team has the option to sell it and gain something from it. EHG wouldn’t have even that.
EDIT: Maybe this will make it clearer to you. It’s Mike’s reply to the other thread I linked above:
And do note that he says it gets locked in “as soon as we make a game build”. Not when we start the game.