We're now nearly a decade beyond the death of plasma, but so many nostalgics wax lyrical about a technology which, while having some good features (like motion and near-black performance) has been outclassed and rendered obsolete in every other dimension.
I'm not nostalgic for plasma, but I have a lot of sympathy for the OP's perspective. Simply put, my Panasonic plasma looks better to my eyes than my Panasonic OLED when watching SDR material.
You mention motion as almost a throwaway aspect of performance, but it's fundamental to the viewing experience. Plasma motion is simply better than OLED - resolving more detail than sample and hold technology can manage without engaging distracting, problematic motion processing.
If most of your viewing is SDR broadcast content, there remains a strong case for hanging onto your plasma television. I find myself watching relatively little 4K HDR content, which leaves me wondering if I was better off before "upgrading."