One of this manga's biggest problems is that, because of the past BS we've seen from this arc and this manga in general, moments that should trigger a reaction get nothing from me. Like when Makarov died, that was supposed to be sad but I didn't care because I low-key assumed he would be brought back shortly after that. It looks like he's dead for real, but it's too late at this point for me to feel the way I should have felt when it first happened.....plus, for all we know there could still be a way for him to miraculously come back (but he should just stay dead tbh). Same thing when Gajeel "died" and Gray legit died for a chapter, I didn't care because I knew somehow they'd be brought back.
So same thing here, given FT's history of "killing" characters for the sake of bringing them back 2-3 chapters later, I already know not to expect Natsu to be down for real (or even Mavis, for that matter), so I don't really care. Which makes sense, since he's the MC, so I would already expect that regardless of whether or not it's FT. And yeah I have to agree with someone above who pointed out that Natsu will somehow be brought back because of Lucy's plan to rewrite the END book, that would make the most sense. Also, judging by how broken Zeref is right now, there's no way he won't be defeated by the power of bullshit, that seems to be the only way to beat him at this point.