What do you consider a “fast swing speed” and why?

Reading a thread about a used set of clubs last night and saw a lot of comments about the shafts being “beasts” or “rebar” because they were 130g X’s (KBS $-Taper) and you needed to be “super fast”. The post was from a newish golfer but even still, what does that really matter? I learned with PX 6.5’s and never had struggles.

I find these shafts pretty soft for what they’re labelled as - am I in the minority there?

Got me thinking, what would the average golfer consider to be a fast swing speed. Would handicap and age change the answer substantially for you?