IIRC I read that the hosts hated one another and refuse to work with each other ever again.

From listening to podcasts done by people involved in those attempts to bring the show back, it seems the show runners/studios in charge didn't understand what made the show good and tried to steer their recreations in bad directions. It does seem like most every host they brought on had good intentions and skillsets, but were held back in some way.

Adam and Jamie were awesome, but I'm certain there are some passionate makers or something out there who could fill the role. It wouldn't be the same, but it could be it's own thing. Whoever the new hosts were must have just been the wrong casting, but also I don't know how much Discovery cared because I didn't know about it and I was a huge Mythbusters fan. I guess I just didn't pay attention because Discovery had already killed everything that was worth paying attention to them for by that point.

William Osman and Michael Reeves + the other youtubers

I remember during the run of Mythbusters either Discovery or History or one of those tried to launch another show to cash in on Mythbusters' success, it was called Smash Lab, and it's clear the creation of this show involved a pie chart titled "Elements of Mythbusters by screen time" and there was one pie wedge labelled "explosions." It didn't last long IIRC.