Agree on all counts. Seixas could probably have done better in his TT because I don't think he prepared very specificially for it, but I think Söderqvist straight up gets 3rd if he races the ME TT.No, definitely not, but worth remembering that Nordhagen came 13th in Romandie too, and he looked worse than his age group rivals both at the Giro and Avenir.
I don't think Seixas was at his best during l'Avenir, but it is only natural that a pro goes better than riders who are taking a slower or more gradual route to the WT, for whatever reason. That's why I'm not sure he's 'miles ahead', rather than just... ahead. As an example, I don't think he'd have come within 30s of Soderqvist yesterday.
I also don't think it's fair to right off the rest before they even turn pro. We have seen Ayuso plateau at an early age and others like Almeida grow year on year.
The step from top 10 in Dauphine to GT winner is definitely the biggest one. And I'm slightly sceptical about guys with a physical build like Seixas, i.e. tall and super thin.