Personally I doubt that anyone who's currently over age 50 will see much change in their SS payouts and (at most) only modest changes in their payroll taxes. We've got about 18 years before the trust fund is set to be depleted, and I expect any changes, once they are made, to exempt people who are within 10 years of scheduled retirement.
The people who will experience changes will likely be Gen-Xers and the Millennials.
^ This. A future Congress won't change benefits for people currently collecting them, or for people who will retire within say, 15 years or so. Won't happen.
The cries of the impending doom of Social Security are way, way, way, way, way, overblown. For example, raising the payroll cap would only affect about 20% of incomes, and then only on that income that above the existing cap. That's not a draconian increase, and it doesn't even have to be the full 4.2% employee share. Some lower fraction (maybe combined with pushing the cap higher) would work too. And/or combined with chained CPI, etc. In short, there are lots options, which perhaps aren't painless, but don't require particularly large changes either.
Also worth remembering that back in 2005 Pres. Bush proposed some broad changes to Social Security, which were never passed by Congress. However, Social Security is actually in
better shape now than it was then even though nothing was done. This despite the fact that we've been through a major recession AND Congress lowered the payroll tax for two years. The reason is that the SS actuaries used conservative models that underestimated overall economic growth during that time period. If the models continue to under estimate growth, there is a possibility that SS will remain solvent indefinitely with no benefit cuts or tax increases. I wouldn't bet on that, but it is a possibility.
But since Social Security has been improving financially over time, and the date when revenues will fall short of project outlays is still a long way into the future and getting farther, we can safely wait a little while and see how things shake out before pressing the panic button.