SS is almost tolerable. It taxes fairly regressively, but provides progressive benefits. It's intended to be a social safety net, for people who didn't establish a retirement income source.
Low income people get far more out of it for every dollar put in, than someone more well off. This approaches ideal. Just as a flat tax is more socially justified even though a flat tax will *still* greatly subsidize lower income, i.e. pay out benefits on a progressive scale. This, we can wrap our heads around.
If you can't make do with the original 3% we were told it would be...well, you're 6.2%, doubled, 12.4% (well less right now for employees). Surely that's enough.
If it's not, fix your spending. Percentage is already adjusted to account for inflation because wage base is moved up in a practical way and it's a percentage of wage base. A percentage already increases with salary norms AND with the economy as it grows. There is no need to keep tacking on extra percentages as a means to keep up with growth. Get ahold of your corruption, fraud, tighten means testing, push back in some areas on states, etc. Keep your costs in line with your program.
Now, the idea of "popping the cap". Sounds catchy right? Just a flick of the thumb...POP! Easy peasy? No, it's absolutely absurd to suggest.
Someone making $5M a year putting $500K into a "safety net", and getting a tiny fraction of that back out, is ridiculous. Wage base exists because it's part of why social security makes *some sense*. Without wage base, it's ludicrious, unjustifiable, and wrong.