There is nearly no possible way for Juventus to be second this season. They are at 59 points and Napoli is at 68 points, that means 9 points difference both teams and there are only six games left. That means, Napoli needs to lose 9 points, as in 3 games of the last six games, does that make sense to you?
It doesn't require losing 3 games, but a few draws and one loss would be enough to shift Napoli position. And Juventus need 4 win streak to catch the point difference. But as you said, that realistically isn't going to happen.We can see Napoli suffering a defeat or a draw, but expecting Juventus to get win streak is something that very unlikely. Meanwhile, Juventus attack line performance is not as strong as a few years ago and this time Juventus only relies on the defense line.
So in this statement I support your opinion that Juventus will not be able to catch Napoli.
To begin with, I would like to understand why you are discussing this possibility?
Firstly, it is obvious that this is only possible mathematically (hypothetically). Secondly, there is no difference at all between second, third and fourth place (for Juventus). But Bologna, which can throw Juventus out of the Champions League zone, is very close - literally one lost match and Juventus will fall to 5th place. Lazio is also not far away. I think the main thing that Juventus is worried about is staying in the top 4.