II do t think any non GT3 911s have future value. The 997.2 owner is pretty funny if he thinks the car is worth that much. The 991 is so dynamically superior, the future will put valuation on the 991.1 --for the reason you say. Last of the NA engines.
And manuals will hold value better than PDK. Once these garage queens sit and the transmissions start leaking --there's no recourse to repair them really. Not like a manual.
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