Why is a 12 ga Parker a "boat anchor" these days?

[MrBojangles]

I recently asked for help with the evaluation of a 12 ga Parker shotgun and one or more responses compared a 12 ga Parker to a boat anchor. Little interest.

Why is this so? The commonality, or lack if rarity, of a 12 bore? Increasing interest amongst women who might find a 12 bore's recoil to be punishing? An increasing average age of Parker owners who might find a 12 bore uncomfortable to shoot due age and increasing frailty and/or health related issues? Less folks interested in side by side shotguns which makes the less common more affordable? Any and all of the above? Or, something else?

I think this applies to all 12 ga shotguns. A Fox Sterlingworth with good plus condition is a $500 gun and has been stuck there a very long time. I know of a 12 ga Ithaca 5E New Ithaca Double that was nearly 100% except the recoil pad was toast from sitting on it in an attic for 70+ years that brought $5750 at auction just last month, including commission.

Thoughts?