This mount is for small antennas with a small sail area. A dish with a large surface area would be chancy due to increased wind load.
If your dish mounting foot was not attached correctly to solid wood with the correct screws, it would be a lot worse. Many installers use lag screws with a portion with a smooth shank. This would only spin if applied to thin sheathing. Since there are no threads in that area, the lag screws provide very little holding power.
The antenna mount industry and the garage door mount and opener industry has long ago adopted fully threaded, hex head drive hardened sheet metal screws. The dbs install industry still specifies and used cheap low strength lag screws not fully threaded along their entire length.