I don't actually believe he was obligated to lay any foundations for the future, as I don't think any thought beyond "this is the best coach available" was made when he was signed. Tavecchio should have known what Conte was going to do (regarding squad selection) when they first sat down, every single one of us knew he would be selecting Giaccherini (and other runners) regardless of the situation, his tenure shouldn't have been a surprise. We all could have guessed he was going to be relatively short term as well, he was on a two year deal and he doesn't really seem suited for this type of job long term, compared to the more intense week to week work of club football.
The FIGC will have the chance to bring in a coach now (someone like Di Francesco imo) that would see through a new generation of talent. Donnarumma, Romagnoli, Berardi etc all depend on it.