I can’t speak for ASCII mode. But DF is not hard, once you learn the game, unless you specifically go looking for a challenge.
The only real difficulty is just how much there is to learn about the game.
If you build defenses, never dig too deeply, and learn the basics of keeping your dwarves happy, you could play a fortress for hundreds of in game years. But that would get boring.
I’d love to know why this is getting down votes.