You apparently do not do improvisation. If you think improvisors make their scenes that easy for themselves, I can assure you, you are surely mistaken, LOL. There's nothing more enjoyable than lobbing out offers to your
scene partners that make them have to scramble to keep up. And in this particular case... you think the DM will just hand things to the players on a silver platter? Heh heh... no fricking way.
DMs know when players are trying to game the system to make things simple for themselves. So even if you skip the dice and just had the DM make arbitrary decisions on whether things succeed or fail based on dramatic tension and narrative conceit... believe me the PCs would still find themselves up the creek without a paddle. And in fact... they'd probably find themselves in even more hot water if the DM could just make narrative choices and not need to rely on dice at all, rather than the other way around.