Thats not entirely true
The flaps can be changed, in the same way blanking plates are fitted.
disconnect the actuating rod, and each flap can be removed with it's supporting bush. 2 X torx screws hold each flap assembly to the manifold.
I ampputated my flaps months ago, I found one that was working loose from it's axle, car had 104K at that time. I cut the axles from the bush, and plugged the hole with an M6 bolt, Nylock nut on the end then distorted the bolt overhang in a vice, and re-fitted the flap bushes in the manifold. Disconnected the EGR also, and run a better quality / slightly lighter oil 0W 40 to keep the turbo flushed at low temperatures, and journals flushed at high temps also. Has passed emissions also BTW.
Sorry to hear abouit the thread originators woes - it's simple - get rid of them, before they strike.