I agree on that point - If my watchmaker can't get the correct parts he'll tell me and refuse to service the watch. I can only hope other watchmakers are as honest.
My friend's watch was purchased at auction and was well out of warranty and I had a rough idea of what a full quartz servie would cost, which was just a bit more than what she bought the watch for. If she had bought this at retail, maybe going back to the brand would have been an option. But in this case it...
I agree and disagree. For my vintage watches, I'm going to an independent watchmaker that I trust. Any watchmaker worth their salt will tell you what they can and cannot do, and that includes sourcing spare parts. Frankly a generic gasket really doesn't matter. However for my modern watches like Lange and Journe those are definitely going back to the manufacturer come service time.I wouldn't have a blanket rule but take it on a case by case basis.
I'm against quartz in general, especially in high-end watches. My lady friend purchased a Bulgari quartz watch which had issues, and the servicing cost from an independent is more than I pay for complicated chronographs, and most watchmaker didn't even want to touch it. If the movement needed to be replaced, or you get the brand to do it, the cost is insane.