Capcom have a boner for platform-exclusive demos and as a huge fan of Capcom let me say I find that practice fucking stupid af. This doesn't really surprise me after their MHW shenanigans last year though. I felt bad for Xbox owners who had never heard of MH before but wanted to try the beta to see if it'd be their kind of game. At least it seems like it's only the first demo that's on Xbox One only, so I guess it might not be as bad as MHW.
I will post this in the inevitable RE2R demo thread too.
No. You might be conflating Turbo mode from previous games with the game's default speed. When this game was first announced we had plenty of gifs directly comparing Nero's melee animations to DMC4's where they are the same speed. Also most of Nero's Red Queen's moveset felt mostly unchanged Exceed-wise in the PAX build.