the diffrence is that we lost some of this players but also replaced them in this 2 years. Hakimi was not there, Dzeko (+ Correa?) came for Lukaku, Dummfries and Darmian instead Candreva, Moses and Lazaro, Perisic and Dimarco instead Asamoah-Young-Biraghi. Then we have not only Sensi now but also Hakan, maybe Eriksen too one day, who knows.
We also had some problems in the defence. Don't forget how bad Skriniar was in the 3man defence. Godin only at the end of season improved a lot, thats why lot of times Dambro played instead them. And Bastoni wasn't that good like he's now.
What i wan't so say is that this team changed a lot. The most important "aspect" is that this guys are a winner team now. They have more experience, played more then 2 seasons together. The coach changed, but i expect them to be more solid then the recent years. Specialy talking about our 3 defenders, Brozo, Barella and Lautaro, they are important leaders now. We will see how far this team will go, on paper we have a realistic chance to be at least a fighting scudetto canditate with Juve and maybe Napoli. Even without Lukaku Eriksen and Hakimi! Many fans are acting like we lost the whole team. This players are still hungry and knows the meaning of "winning", diffrent from 2011 for example, where most of them already won everything.