Rust is about 7.6 times more dense than gasoline so rust flakes and rust grit tends to "sink like a rock". Rust powder is generally too fine to plug the system.
The majority of tractor operations on rough ground will cause the rust to skoot a little on the bottom. More active skoot will occur as the tank gets low on fuel but the rust is very reluctant to launch off the bottom. Sediment bowls do not launch sediment and neither does tank sloosh launch coarse rust generally speaking.
A powered refueling nozzle may cause the flakes and grit to experience much greater agitation that sloosh and thus get picked up off the bottom until the refueling stops or until the fuel gets deep.
Pointing any refueling method away from the standpipe will produce near zero chance of flakes or grit coming down on the standpipe's opening.
All the gasoline around here has ethanaol which absorbs any water but can cause other problems.