I haven't seen anything he has done at the Giro so far as an indication that he's going to be worse at the Tour this year. Of course there's not much pointing to the opposite either, but I hadn't expected he would drop his best ever numbers on Blockhaus anyway.
There's obviously a chance that Visma have been over confident following his first races this season and Almeida's withdrawal meaning that he's slightly weaker than he could/would have been otherwise, but then we haven't yet seen that anyone will be able to take advantage of it and dethrone him.
If Seixas or someone else is really able to challenge him for second in the Tour, it could also mean his odds of winning it will actually improve. Whether he finishes second or third doesn't really matter that much, unless he fails to win the Giro, or the Tour win gets reallocated for some reason in the future, which I doubt will happen. If Pogačar doesn't start or finish the race, then it would naturally be a different situation, but being in the top 2 or 3 for five seasons or more is not a bad run, especially not if you can keep winning in the other GTs.