If you get launched at 55-60kph, and then pedal 2000W for 10 seconds, what speed does you have across the line? Must be in the highway ballpark. Even if acceleration gets exponentially harder. V in the formula is squared. Air drag itself is worse than that.
One day in my off-season, being a slacker in terms of pro racing, I did some national MTB racing, I tested:
82kg, 506W maximum. This was a ramping up test that took 20-25minutes. I had been averaging 506W or so the last minutes when I gave up during the 520W block. Running shoes on platform pedals, too short cranks, doc wanted a steady cadance so I picked 98 from start, 110 might have been better.
It was not tested in this period, but I was guessing my one-hour power would have been around 400W. I was NOT living like a pro athlete, and barely looking at my diet. 25 y/o. I was figuring I could go over 550W Max with more dedication, 430W or so for an hour effort.
I was not particularly fast though, due to excessively long legs. Too much wind drag. I would make a difference compared to my competitors on light uphills, or at high speeds with tail wind. Head wind was a problem when faced with equal competition. Crits hurt, I was dropped a lot. Ended up TT'ing them at times to stay on the same lap for an hour. On hilly MTB courses where things were gradual yet brutal, I was pretty darn quick.
I believe that with the right genes, good numbers can be reached. There are just too many pro cyclists who think they "deserve" such numbers. No such thing. You make the best of what you're given.
Sports is in the basis not fair.
I'll make a short statement that IMO most pro's fail to set their bikes up correctly. Try to ride up Alps with their Crit slash Classics bike. If that bike is set up wrong to begin with, Alps are going to take some time and teeth gritting. Enjoy the bus.
For a big guy, I could climb with the best of my class. I like that bikes are the same weight, regardless of the rider weight. Less bike weight per kg for the big guy. Another reason a bigger guy with the same VO2max will beat the lighter guy.
Big guys are just told they won't ever be able to climb. TT specialists the same. I don't get the big time diffs in TT's, as the high speeds should even the playing field.