What makes Samurai Jack work is that they don't try too hard.

It's also worth remembering that one major difference between the two shows is that Samurai Jack season 5 is being worked on by its original creator, while PPG 2016 has no involvement from any of the original crew members. In all fairness to CN, Craig McCracken confirmed that CN DID ask him to work on the reboot before they started production on it, but he was unable to due to his contract with Disney preventing him from working with any other studios for a select number of years. I imagine if McCracken was able to work on PPG 2016 the show would have turned out much better.

Meanwhile I think Genndy has since left Sony after the plans for a Popeye movie unfortunately fell through and they opted to greenlight the Emoji Movie instead (I know if my passion project got passed over for the Emoji Movie I'd be pretty damn upset too).