Odd decision.
I think they want to kill the show for some reason, possibly to fund some politicial stuff to air. I get the feeling the cast was fired the last day of fling or something like that since they didn’t get to do a on air goodbye or special.
No really. It’s been years that Mythbusters has ever challenged a myth that was really compelling.
After the third season, it seems that they settled into finding things to blow up.