>>> It would seem to me that if you made all payroll eligible for taxation, you would only be impacting those well into the upper-middle class, and would ensure solvency for at least 75 years.

Assuming no change in economic behavior.

Incomes at that level can be restructured into a variety of vehicles (stock compensation, deferred compensation, stock options) that would not be a subject to SS.

You gain more by enabling job growth.