Look, I know my browsing will be in a huge database that nobody will look at it.
The problem is not correctly posed as "nobody will look at it." This isn't a people problem.
What "looks at it" is computer systems, programmed to look at it. What a human would consider "lost in a sea of data", a computer will have no trouble finding, characterizing, and reporting back as "this is the data you were looking for" to any interested inquiry, perfectly formatted for immediate use / subsequent action.
So the day they make your particular fetish or recreational substance / entertainment / political stance / religion / etc. a crime, that data will immediately identify you as a vulnerable citizen. Now it comes down to what use can be made of you. Porn sweep to impress the mommies? A little pressure to get you to do X or Y? Filling the need for unpaid slave labor in prison factories? Soylent green? (I hate that damned movie, but...)
In the US, the constitution explicitly forbids -- both to the federal government and that of the states -- going back in time and making crimes out of actions that were not crimes at the time, or increasing punishment along the same lines. These are the "ex post facto" provisions. In recent decades, a spate of such laws have been crafted and put into broad use, treating the constitutional prohibitions as irrelevant. Generally the mechanism used has been sophistry ("You absolutely will not sell hamburgers" ... "Why, that's not a hamburger! That's a ground beef sandwich!" ... "Okay then, carry on.") and pandering to intentionally crafted, hysteria-induced mommy fear (Terrorists! Drugs! Think of the children!), which is often spiced with not-very-subtle appeals to jingoism, superstition, and classist notions.
Unless the citizens can control the government, a capability US citizens no longer have, this kind of cancerous spreading of unauthorized and forbidden exercise of power is very likely. Your data stashed in some database today renders you vulnerable to any part or parcel of perfidy by any state actor. The only sure way to prevent this is to keep your data out of these databases in the first place. And it looks like you've forfeited that option. Sorry.