Total agree. I think tires made today have different compounds than those you have on your car. Your older tires may also be showing a resultant loose of performance because of the many warm cold cycles they have been through, and the accumulated mileage to the structure and tread grip. Thing is not only summer tire rubber compounds have changed over the past decade, so also has the all season. If I lived in an area with consistent temps below 45 for months during the winter and did not want to have two sets of rims/tires I would only run all season tires on the road.
Many of the top end tire manufactures "secrets" to the cutting edge compounds have been found by most manufactures. As time has passed the (some consolidation in the industry also contributes) tire compounds between manufactures has become less differentiated. Tread patterns and the internal structure is another story. Road conditions are so very important; If it is wet SLOW down and the public roads are no place to be pushing performance anyways.