Say what you want about the past world record, and your argument is circular for the second point. the 3rd point is where you are dead wrong. You assumed that 48 is HTM. It is not. Roux averages 48 moves STM and Waterman averages 40-45 moves. Some rouxers do believe that roux's movecount could be lowered to 46 for advanced solvers, but either way Waterman is less moves. Ergo-wise, you might be right, but I actually enjoy waterman ergo.
As for why your argument is circular on point 2... You said that just because one person is fast with a method does not make it good. Then how do you justify a new method ermerging. I think that every method has to start somewhere, and I also think it only takes one person to prove it is viable. If only one person is fast with it then it isn't a good method and no one should use it, so therefore no one uses it and it is a bad method because no one uses it and it never gets fast so it must be a bad method because no one gave it a chance.
Also, I'm not sure who said this, but someone said getting a PB 1/2 your average is unlikely, but I disagree. I know someone who averages 12-13 and has a 6 as a pb. There are plenty of people who have very fast PBs compared to their averages. Think about top solvers, they average sub 6 on a good day and some of them have sub 3 PBs so that is 1/2 their average. A silly point, but I had to refute it nonetheless.