If this was announced back when Ultimate was first revealed, I may have been more upset about it.
But now, after getting so many dream characters in this game (especially Banjo), I'm totally fine with it. Minecraft is such an enormous and influential game that it makes sense to be represented in Smash, and while I know a lot of people are pissed about this inclusion (which I find kind of hilarious, honestly), I've seen a lot of people really excited as well, especially the younger crowd. His moveset looks weird and creative enough that I'm excited to learn more about it and see how he plays (you can actually build?! What?!) and I like how the stage incorporates different biomes and locations.
Sure, he's visually jarring compared to all the other characters, but it's honestly so weird I kind of like it. I actually lost my shit a little when it did the dramatic zoom in on him activating his final smash because it just seemed so surreal to me.
Besides, we still have four more characters to go if you felt let down by this choice.