These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Crash Bandicoot: The Wrath of Cortex
Harsher in Hindsight: "Tsunami" has you evading a small tsunami in an Asian themed area and then exploring the flooded remains as a gem pathway.
It's the Same, Now It Sucks: The biggest gripe players had with this game was that it was a carbon copy of Warped!, only adding new levels. One of the reasons Naughty Dog closed the door on Crash was because they felt they took the concept as far as it could; the negative reaction of Wrath due to precisely this reason aided the notion they probably made the right move.
Nightmare Fuel: The Droid Void. The part when you enter the mech and have have to go through darkness is just....
The mech. Clunky, hard to maneuver and easy to get hit as, it likely would have been easier and more fun to play the majority of the game as Crash himself.
Similarly, Coco. Anything she can do, Crash can do better, and one of her levels is a Crash level made simpler so that Coco could do it.
The grates in Droid Void, Weathering Heights, etcetera. They are so slow and irritating that the best way to do Weathering Heights' time trial is to actually give up invincibility in exchange for being able to run across the floor and skip the grates. This enables you to halve the Platinum time, and then some.
You only spend six levels (of thirty) playing entirely as the Crash platformer-mode we all know and love. The other 24 levels are all either played as Coco, or spend at least half (if not all) of them in a vehicle of some kind.