.A tv aerial and a sky dish are two different entities when it come to alignment needs and rigidity.
A tv aerial as a very large leeway in how much it can move before it loses the signal from the transmitter it is pointed at.
A satellite is parked 22000 miles away in geostationary orbit.Why this distance?
The earth is continually rotating as we all know giving us day and night,satellite at 22000 miles is orbiting the earth at such a speed it matches perfectly the earths rotation rate so from our our point of view making it stay at exactly the point in the sky.
So the adjustments on a sky are minute,so a dish bending around in the wind is no way going to keep signal lock