I agree wholeheartedly with what you are saying; when you expand on what you mean past just 'there are too many people' and actually suggest realistic meaningful solutions like you have here, I highly doubt that most people would 'accuse you of all sorts of things'. It's just that when you simply post 'there are too many people' this implies there should be less people, to most people they would interpret that to mean in an immediate sense, aka unaliving them.
Now that you've expanded on what you had to say I can see that clearly isn't what your intention was to convey. I would just like to say though that considering human population level is not a factor we can control without death or reducing birthrate, and birthrates are already reducing globally, you should be able to see why many would assume you are advocating for the other option.
I understand the hesitation completely as I also dislike the shonen reincarnation plots but I do think it differs quite a lot in that one piece is and has always been about inherited will, and that hasn't changed at all with the sun god reveal.
Luffy has the inherited will of Roger, not nika, I would argue that in terms of blood line nonsense luffy has a special bloodline from when we find out his father and grandfather? So far before the new world. Literally as far back as logue town. But even then, its again actually about inherited will, since luffy inherits Rogers will from Shanks, completely fucks off his grandfather's will. And isn't even aware he has a father, he acts of his own accord, the will of nika doesn't manifest until awakening. As far as I'm concerned, devil fruits and haki are all expressions of willpower in one piece. Also it was never about ordinary people, there are specifically 'ordinary people' on the crew within the first five members to contrast with the rest of the crew being clearly insanely superhuman from episode one. The characters are chosen by fate by having inherited will from those that they idolise and emulated at the right time. Which is more or less exactly how real life (narritively) works anyway.
Sorry for rant or w/e but 'the chosen one' trope I agree gets boring but... Idk it doesn't fully apply to Luffy. But I won't pretend there aren't some elements that apply to Luffy, Zoro, Sanji, Nami, Usopp, Robin, Franky, Brook and Jinbei. I mean listing the main crew they are all fitting of those archetypes in different ways and always have been?
If we talk of 'the special one' that applies to any and all exceptional people real or fictional. So avoiding that you would just be writing a story about unexceptional people doing normal things. Which is all well and good, but don't be surprised when you don't find that in shonen manga. 😅