Flooding causing electrical problems

Has anyone had experience with electrical system flooding? Twice now, our BMW wagon has had electrical problems caused by “obstructions in the sun roof drainage system” (according to the dealer repair). I happen to know that Audi is settling a class action suit for a very similar problem. This has proven to be a very expensive repair, and I wonder if it is a design flaw in the car.

Much depends on where the car is parked. If it’s near trees or in an area prone to blowing dirt, leaves, etc. then this is not a manufacturing defect.

When it comes to vehicles and class action suits, the fact a suit is settled does not mean there is really a problem with the car. It only means that the bean counters figure the least expensive way out is to shell out money in a settlement rather than take a chance on a clueless jury awarding billions of dollars in a judgement.
Now and then a suit is justified; the majority are not.

Are there any trees, shrubs, or whatnot adjacent to where the car is parked?

No. Trust me, I thought of that.