So... watched the video and the whole thing seems to be
'it's bad because marketing.'
There are a few legitimate problems like not seeing far enough ahead, but for 99% of the problems they showed they could have solved the problem by simply rolling, one of the most fundamental moves in the game (and he's a hedgehog. Which rolls in a ball to protect itself. You want a th*rking diagram here?) Even then, the game doesn't punish you severely, if you have rings you can usually scramble to grab a couple to keep playing. If the enemies were hidden and getting hit instantly killed you then I'd have more of a problem.
They criticise the open level design as a bad thing? One of the main reasons that the early Sonic games had so much replay factor was the sheer number of ways you could get through the levels. They felt more like places to me than Mario's flat worlds with some obstacles in the way. By going through the game carefully, hopping from platform to platform you had one level, by going fast, remembering to curl into a ball and jumping right you saw another level. By really taking your time to explore, jumping at every wall to see if it had hidden passages you saw another.
They also criticise the story. Let's be honest, if you're judging most 8-16 bit games on their story they'd almost all be awful.