While I'm still relatively new to watches (only around 1 year) I don't mind having both but in the end, I keep my mechanicals longer.
Why?
1. Having something different than the general public
2. Nice mechanical movements look very beautiful
3. The joy of the sweeping second hand, especially with 28,800 BPH movements.
4. Usually makes for a thick case

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5. Theoretically, they can last forever and are serviceable.
I doubt quartz will become the only affordable route for watches. I think once the ETA squeeze goes into effect, I think (read: hope) some other companies step up and make other automatics. I'd really like to see a market with more than 1-2 dominant movements, I'd love to see (won't happen) each company have their own movements, or at best, have 4-5 different movements. While developing movements isn't cheap, forget easy, I'd like to see the movement industry diversify. But if that industry follows the same route many others have, consolidation is usually the end result...

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In order for me to buy a quartz, it has to offer something special. Either be highly accurate or be kinetic, or a highly jeweled one.
In the end, I have both and I'll continue to buy both. It isn't a deciding factor in buying but I do like the mechanical mechanisms best.