Antonio Conte is consistently underestimated yet he keeps proving people wrong as one of Europe best football managers. At Chelsea he won league but his success mostly does not get credit it deserves. More recently he led Napoli to league title even after boldly letting go of important players not once but twice in one season. This shows his strong belief in his tactics and his ability to get best out of his team even when others would be scared to make such big changes. Conte success with Napoli truly cements his place as top coach who consistently helps his teams achieve their full potential and he is still probably not recognized enough for it.
No one underestimates Antonio Conte, it's just that many people doubt that Antonio Conte can make an impact on the Napoli team that quickly, it's really an extraordinary thing when in just one season a coach manages to make changes and immediately win the title, it's really extraordinary and it also proves the quality of Antonio Conte's coaching.
So for now Napoli will be highly regarded not only in Serie A but also in European competitions because after Antonio Conte's impressive first season of course he will also do better next season, I think it's very likely.