This is not the type of thread you probably expect on a BMW forum but I feel honour bound to share my experience but I guess it will be removed fairly quickly.
Honour bound? I would rather say you are very frustrated and wanted to vent!
You purchased three of them, so the issues mustn't be so bad.
I understand that you had some negative experiences with your bikes and you have lost your patience. But to generalise? That's a bit rough.
Why don't you just sell the GS and purchase a light and reliable Japanese bike? I wouldn't touch a KTM, as you might get similar issues.
But you won't find all the electronic adjustments that you'll find on a BMW (or Aprillia and Ducati), as the Japanese don't make fancy. They make reliable and boring.
Of course that is not always true, as I had very many issues with Japanese cars and I have owned a few.
It very often comes down to the dealership and how well they work on your particular vehicle, as mentioned before.
Sometimes there are electronic gremlins, as it happened to somebody I ride with, but it seems fixed now.
BMW GS are the best selling Adventure bike worldwide and they have sold over 500,000 units in over 30 years. They have pushed all the others to come up to a very high standard.
I am not saying they are more reliable than any other brand, but it is unfortunately very true that more modern vehicles fail more often.
The simpler the tech the more reliable the vehicles are.