what is it you do not understand Trumpet Power?
se earlier answers regarding pixels and charge, s/n, there is no enlargement regarding a charge, IT IS a optical question if the charge is equal from a smaller or bigger sensor and with the same resolution
it requires more from a lens to reproduce the smaller sensor's pixel density
and 2 examples , it requires 1,6 more of a lens for APS sensor compared to the same same resolution from a 24x36mm sensor , and the same if you compare a 24x36 mm sensor with a medium format sensor, it requires more from the lens to reproduce a 24 x36mm sensors 40MP than it does from a medium format sensors and 40MP
and read now back and look at what you have been writing
Mikael, if you need a lens that's 1.6 times sharper to get the same image out of APS-C than out of 135, then it should be self-evident that, with lenses of equal sharpness, the 135 format is 16 times sharper than APS-C.
In other words, larger formats are sharper. Sharper lenses are sharper, too, but you can combine a sharp lens with a large format to get an even sharper image than you can with a sharp lens and a small format.
That's what "all else being equal" means. If the lenses are of equal sharpness, if the sensors have the same S/N ratio and other technological characteristics, if everything else is equal, the camera with the larger format will be sharper.
This is what I've been writing from the beginning. If you still don't get it, then at best, your English isn't good enough for you to participate in this discussion.