Seriously, I never want Italy, Germany, Portugal and France to be out of the Euro at the round of 16 stages. I consider all of these were upsets.
I won't be able to see many of my favorite players in Quarterfinals matches. I don't know about other people here but this made me really sad.

Italy? Italy is still there, right? Their quarter final match is against Belgium on 3rd July. It is going to be a tough task for them, but I am hopeful given their recent form. On the other hand, despite the presence of star players such as Romelu Lukaku, Belgium has been facing a lot of issues related to team cohesion and coordination. And in your list, Germany and Portugal were just unlucky. They got very tough opponents for their PQF matches. Not the case with France though. They should blame themselves for the poor performance against Switzerland.
No, I believe a 1-0 win for Belgium is a decent result, I personally am not so sure about Portugal even though there is CR7 there. So yeah, the unlucky result for me was only about Germany and France, previously I predicted France might get to the final but they were knocked out early by Switzerland and it's a team that I don't think really counts for getting through to the quarter-finals. But even so, I'm not sad because with Switzerland and Ukraine qualify of course it will make this competition more difficult to predict, because dark horse teams like this could cause another surprise in the quarter-finals later.