I agree with you; the biggest surprises of the tournament so far have been in Group E. If Belgium suffers another defeat, they may not be eliminated because they can still qualify out of the group as the third-placed team. However, this situation would make their job harder. Considering today’s performances, it is possible that Ukraine will finish last in the group, and Belgium will end up third.
This is just their first game and I think it is way too early to judge them base on this performance today alone, The game is still open and Belgium can still come out top in their group if they win all their remaining matches from here despite that they lost in today's game but the correction may come in their games ahead, and I still doubt Belgium won't qualify for next stage of this competition.
As an individual spectator of the game, I really lost confidence in the Belgium team during the world cup. I wasn't just impressed because the pressure of Belgium I used to know was not there. Even when KDB gave his honest review of the Belgium team, he said that the squad is not young. And that was true as at the time of the world cup. I didn't watch this first match, I would have checked how young their squad is now.
From the beginning of the Euro, alot of goals came but it seems that the goals have seized coming. England managed to score 1 goal while France was gifted 1 goal through an OG. This means it gonna be a tough and surprising Euro.