Playing the devils advocate if a heavy platter is not rotating
at the correct speed is it then more difficult to manage/correct?
Correct. Which is why the simplistic answers are... simplistic.
Merely turning the turntable on- just spinning the platter, not even playing a record- sets the entire system in motion and vibrating. No bearing is absolutely perfectly smooth. Nor any motor, nor belt. All this stuff is vibrating like crazy making noise the cartridge is going to pick up, and we haven't even started playing a record yet.
People need to understand mass is not magic. If all you are doing is adding mass to an otherwise identical platter then yes, that is better. At least in the case of the ones I have heard compared side by side.
But who says we can only change the one thing? That's why these questions that like to look at just one aspect are so tedious. The only good thing about them is every once in a while they serve to maybe help make people aware the world is nowhere near as simple as these kinds of questions make you think.
Besides vibration there is speed stability. Don't care how massive the platter, dragging a stylus through music creates constantly varying braking loads. And yes it does matter. Some motor controllers allow user changes to response curves. One setting the controller responds quickly with a lot of torque, another slower with less, and all kinds of things in between. It is easy to hear the difference even with a very massive platter.
Mass is not magic.
This sort of drag, you don't hear it as pitch but rather a loss of immediacy or dynamics.
My last 2 tables, one was high mass, 25lb lead shot filled platter 3" thick. The other platter maybe about 3lbs couple three different materials an inch or so thick and smaller diameter as well. To hear the high mass guys talk this should be no contest, and it isn't. The smaller lighter platter kicks butt, far more dynamic, much better timbre and timing, just across the board superior.
Even something as seemingly simple as a platter there is a lot going on.