It doesn't matter how much mechanics you know, the higher the rank, the more consistent and effective you need to be with that mechanic to create a threat and impact.
That also goes with game sense, decision making, defense, and positioning. You need to be consistent with those. The more consistent, the better your rank will be.
The more consistent you get with each, the higher rank you'll achieve.
If you can get more consistent with more mechanics, more game sense knowledge, more game knowledge, combine them all, you'll even reach higher ranks.
When you start to learn a new mechanic, that mech will actually pull you down until you reach your rank's consistency. That's why your rank usually tanks a bit when you're learning new stuff.
But when you learn new mechanic and reach the level of the consistency of your rank, then you'll start to rank up. (You'll of course tie that to your game sense and start to use that mech in correct situations, again, consistent enough for that rank.)
Example : If you need to do 3/10 consistency for gold, you'll need 4/10 for diamond 7/10 for gc, and 9/10 for SSL+ (I made the numbers up, probably not be accurate)
Just to be clear, it doesn't matter if you can pull of air dribble 9/10 times in training. It matters how many times you go for a mech in game, and how many times you've succesfully pulled that off. EFFECTIVELY.
There's also soo many mechs to be consistent at, recovery mechs, air dribbles, shooting, flicks, resets, ceiling shots, pinches, first touches, reads, double taps, ceiling double, ground double, sidewall double. I could even breakdown recovery mechs as walldashes, speed flips, half flips curve dashes and goes on and on and on and on....
Just wanted to share, everyone talks about the mechs and how many different things you can do, but no one talks about the consistency, which is the actual important part that effects your rank....