This is an urban legend hawked by anyone who has never disassembled a tank.
The fuel is taken at the lowest point, just a few millimeters above the bottom, frequently via a strainer that filters only large debris, nothing but debris.
it's very fair, often and more and more debris of belts that can clog the strainers.
The filling therefore has absolutely no effect on the intake which is always down, because the water is heavier than the fuel, so stagnates at the bottom, at the point of capture ...
even there, the fuel pump will not syphon only water, at most it will crawl the engine.
PS: On the other hand refuel with a tank bottom almost empty of the gas station is a good way to have problems. But there, impossible to know, is the lottery.
even there, except to have fuel of very bad quality, the filters (to change regularly and that some forget to do) with gasoline or gas oïl avoid these problems, except on vehicles of 50 years.
"We make science with facts, like making a house with stones: but an accumulation of facts is no more a science than a pile of stones is a house" Henri Poincaré