Playing cash requires quite a different mix / balance of knowledge / skills. To give only a few examples, since the blinds don't rise and you are (or should be) fairly deep-stacked at all times, implied odds
are always a consideration instead of just early on in MTTs. Also, you should never be in a position to play shove-fold poker, and your opponents won't be very often either. Stealing blinds to stay alive doesn't happen much either.
Add in that your table composition tends to change less, and you generally have more scope to gain from building an image and then changing gears.
And because money is money, concepts like ICM, changing chip value over time and the value of your tournament life don't matter.