Unreal has been in a different league basically since its inception. Compare the original Unreal engine to its contemporaries like Quake or Half Life and it’s amazing what they could do, if you had a box that could run it.
The difference between Unreal and Unity is Unreal has a sustainable viable business model (I think I’ve come to the conclusion that there are no “sustainable” business models under capitalism, what with demanding infinite growth and lal that). Epic Games develops their own games; the development of Unreal Engine has pulled its weight as a component of Fortnite and such. Same thing with Valve; I don’t think they ever bothered to charge for developing a game in the Source engine because they made their money for engine development through Half Life 2, Portal, TF2, Left 4 Dead etc.
Unity on the other hand doesn’t make and sell games, so they have to either directly charge developers (which they both do and don’t) or they operate their own adware nonsense. And neither of those revenue streams are enough. Which means they don’t have a viable business model. So they pull a stunt like this to hasten their inevitable bankruptcy.