[100k]

The reason why wealthy retirees get Social Security and why the tax is capped at $106K/year is the same: it's to prevent Social Security from being a welfare program for poor people

Since everyone gets Social Security, this makes it much harder to get rid of. This was an intentional feature, and it has worked -- look at the fate of welfare programs devoted to poor people. The poor have very little political power and are easy to "other", making programs for them easy targets.

The tax cap is in place because Social Security payments are based on the amount you paid in. By capping the tax, this limits the payments necessary to wealthy retires which would make Social Security very expensive.

Anyway, nothing you're suggesting is totally unreasonable, but I think it's important to recognize that there is significant amount of political and policy savvy that went into to designing Social Security. It is both a very popular AND successful program.