You didn't answer the shipping question.
Because it is just a pathetic distraction from you to pretend you are not wrong.
Again, when the objects are not fully submerged it is quite apparent that they won't displace the same amount of water. But when they are, they do.
You're 100% wrong but you'll never see it because you don't want to see it.
You sure do love projecting your own inadequacies don't you?
Pretty much everyone can realise (at least if they bother thinking about it) that all your claims about your magical air are pure nonsense with no connection to reality at all.
You just refuse to see it because you don't want to, because you hate the globe so much you will do whatever you can to dismiss it and things associated with it.
For example, any sane person can see that in reality, 2 objects of the same size (e.g. 2 balls with diameter of 20 cm), will resist changes in motion by different amounts, i.e. it will require a different force to accelerate them. They can see that the denser (i.e. more massive) object resists more.
This shows them that it is not merely the result of air pressure like you claim.
If it was, then the 2 balls should resist the same amount. The only thing that would change that is if there is any air inside the object, which you claim the lower density object has. But that simply means the lighter object is displacing more air and should resist more, not less.
And we know this last part in 2 ways, one is that it is simply nonsense to think that less air (eventually resulting in no air) would produce more resistance. The other is that by using a larger object, which displaces more air, we get more resistance, so if displacing less air caused more resistance you would have a massive contradiction.
Meanwhile, the simple idea of inertia actually makes sense and matches what is observed.
Attempting to accelerate any mass will result it in resisting, simply because of its mass.
If you were to take 2 such objects and join them together, the mass would increase and so would the amount of resistance, with them being proportional to each other, exactly as observed.
And even worse applies for your nonsensical attempt at replacing gravity, where you can't even explain what causes a pressure gradient in the atmosphere to exist in the first place, nor why this pressure gradient typically applies a force in the wrong direction, nor how this force is magically applied to each bit of mass to establish a pressure gradient, rather than simply being applied at the top and crushing everything.