I read and downvoted. Because of multiple statements in that post that are just wrong. And baseless attacks on Psyonix.
It's not that Psyonix didn't want to investigate the problem like you claim. It's just that nobody can replicate it. How are they supposed to work on a bug that so far and despite being supposedly here since the start we never get even a proof it exists ? It shouldn't be that complicated, make a macro with like jump and air roll. If the inputs are really delayed you should be able to measure the difference.
The "decline in playerbase" is a baseless claim, until July and the next infographic we can't know. But since they are still in the top of steam sales you are probably wrong.
You're also delusional of you think that a large percentage of the playerbase can't rank up because of this. If it was the case it would cause large outrage and that's really far from happening. I want to belive that it exists, really, but so far the fact that in almost 4 years nobody has been able to show even a slight proof is hard to get over.