Aren't we all forgetting the two key determinants of how fast you go?
The only single determinant of how fast you go is how much work you put in to going fast. The problem these days is that people assume that they can buy their way quicker, which is super for the deep section light weight aero sellers, but has very little influence on the actual speeds that people ride at.
Even the speed merchants from here will suggest that such and such an upgrade has 'massive' benefits, with very little in the way of quantifiable evidence to support their assumption.
One would assume that with all the aero and weight advantages available these days, that TT records would be tumbling every week...
You'll get quicker by training to go quicker, not by buying stuff.