Sorry, I disagree. Conte had a lot of young talent available to him, he decided to ignore it and go largely with mediocre experienced players who suited his style more. Players like Insigne, Verratti, Jorginho, Bernardeschi, Berardi, Florenzi, etc were all considered very gifted, yet Conte focussed on others. He went for short-term-ism, which has been typical of most Azzurri coaches, and left the Azzurri in a worse situation than he found them in. Don't get me wrong, Conte did well with the Azzurri and you will find many posts from me praising his work... but its wrong to say he did not have talent to work with. He just made different choices. If he choose to play Zaza over Insigne and Giacherrini over Bernardeschi/Florenzi, you can't complain he had no talent available to develop.
Mancini made different choices. He focussed on giving talented youngsters regular playing time and develop a new team/squad, and ignore older players like De Rossi, Candreva, Parolo, etc. Players like Barella, Sensi, Zaniolo, Chiesa, Pellegrini, Tonali, etc have grown with the experience in the NT. Infact Zaniolo got a call for the NT even before he had played a single game for his club at the senior level, that in itself defines this new Azzurri. Part of the growth of these kids and the fact that they play with assured confidence actually goes to Mancini, coz playing for the Azzurri at such an young age gives you a different level of confidence. Even players like Jorginho, Insigne, Bernardeschi, etc who have been at the top of their game for a while have become regular starters for the Azzurri only under Mancini, before that they were used as largely bench/rotational players.
IMO Mancini has already achieved more than Conte for the Azzurri, even before playing in the Euro. No one expected this young, experimental side to do so well so soon. Whatever happens in the Euro's next summer will only be a bonus, the real fruit for all this work will probably be seen in World Cup 2022 when many of these kids will mature together and hit their peak.
I agree, they have achieved nothing yet. All these records mean nothing. The only thing matters is how they perform in the Euro or WC. And they haven't played one yet.
I am just commenting upon the transformation in terms of talent and style of play. I have been a Azzurri fan since I started watching football as a kid - 1982 WC was what did it for me. And I have followed Italy ever since, with 2 decades of "golden generations" following by a steady decline since 2006. But in these many decades of following Azzurri, I have never seen anything like this. I think Mancini is building something beautiful, and whether they succeed or fail next summer, there is new life in the Azzurri. It warms my heart. It gives me hope. Forza Azzurri!