Some say so. But we know now that Rominger was heavily juiced during those years, and Duc and certain others were on the down swing of their racing days. So i think it was a combination of factors.
I equate it to the Lebron effect. LeBron is consider the "King" of the NBA, but he came at a time when there were a handful of great players. VS, the Jordan era, Jordan was the King and still is. And when he was playing you had many many handfuls of players who were in the top. Bird, Magic, Boggs, Meta, Mchale and a good 48+ more who could perform. During LeBrons run, there were maybe 5? And they weren't as good as him. So he was alone and that's why he was the king. And then now you have more good players during his run and they are just spanking him-Steph Curry! Incredible player.
I think road racing had the same rollercoaster ride of good riders. Just like when Lance was racing. There weren't as many great riders. A few, but no were near the amount during the LeMond days.
I think that combination of things affected the PR fork and innovation in the road world. If you look at road racing, after LeMond left, what innovations happened? None. Lighter or more simplified versions of what he brought forth, but nothing really.
Electrics? He did it first.
Carbon frames? him
Ti? Him again
aeroness? Again, LeMond
Power meters? He was using the first SRMs made
Suspension....LeMond.
LeMond really changed cycling in massive ways. And after him, there weren't as many if any real innovations in the cycling world. Can anyone mention any?
So I think it was a combination of factors.