Conte took over a team that were a total **** show, nowhere near the CL spots.
I don't really see the "top class talent" you're referring too. Lets look at some of his players before he arrived.
Courtois - underperforming, a lot of Chelsea fans still moaning that Cech was sold.
Alonso - best known here as a player who couldn't hack it at Sunderland.
Moses - doing nothing in his career, a bench warming winger.
Cahill - **** (and still is tbf)
Azpi - playing at right back.
Luiz - thought of as a total joke in this country.
Terry - end of his career and hasn't played this season so not really relevant.
Cesc - washed for years (barring his first 3-4 months at Chelsea), was terrible last season.
Matic - washed (only really had one good season anyway), was terrible last season.
Willian - poor for years, altho there was that spell when he was nailing free kicks on the reg.
Pedro - considered a flop signing.
Costa - was coming off a bang average second season at the club.
Hazard - a complete joke last season, although probably the first "top class talent" outfield player on this list.
Kante - the other "top class talent" on this list.
Conte has taken that group to a likely double, probably with 90+ points in the league as well.
Nearly all these players have either changed position, improved massively, or in a lot of cases performing better than any of us thought were possible.