The ISS is about 1.5 times the size of a 747.

A 747 at crushing altitude (5 miles) is a dim gray spec smaller than a pencil eraser held at arms length.

The ISS is 50 times farther away, 250 miles which would make its angular size magnitudes smaller than the human eye could see.

When we see the light in the sky they tell us is the ISS it is the brightest object in the sky aside from the sun or moon. It is a steady bright light, brighter than any star.

When we are shown footage of the ISS crew doing a space walk or just outside footage of the ISS it is no brighter than a normally lit scene anywhere.

The ISS has a course that is as reliable and predictable of any wandering luminary aka planet.

There is ZERO chance that we are seeing a man made object 250 miles high in the sky.

Seeing the ISS cross the entire skyline as a bright light is not the same thing as when someone catches the supposed ISS transiting the sun or moon face. Nobody ever sees the ISS approach the sun or moon face or exit it. This is just a parlor trick NASA is doing probably with smaller closer aircraft.