[mosfetarium]

There's definitely been improvements in level editors for existing engines. Hell, if you want to use those old editors, there are even plugins like HammUEr, to use Hammer with Unreal 4 and Qodot to use editors like TrenchBroom with Godot.

But I will say there was something particularly special about level editors coming with the greatest games of the day back in the 90s and early 2000s. Not only was this extremely accessible as it meant you could just learn level design, and not the rest of game development, but it meant you got to learn level design for your favourite games, something particularly enticing to young people. You also got a bit of a built-in audience.