For those adversaries, you need to work out a careful balance between deterrence, solving problems (e.g. resource abuse), and your desire to “win”. In extreme cases your best strategy is for your filter to “work” but be broken in hard to detect ways. For example, showing all but the most valuable content. Or spiking the data with just enough rubbish to diminish its value. Or having the content indexes return delayed/stale/incomplete data.

And whatever you do, don’t use incrementing integers. Ask me how I know.