The error has nothing to do with tags. I've sometimes encountered the error when trying to load the forum or simply opening games.

The error is a side effect of the measures Itch has had to take due to the multiple DDoS attacks it has suffered.

I am also consistently getting the same error the past few days whenever I try to search with three or more tags/filters, and not when I search with fewer.  

I realize that that error pops up _occasionally_ in general due to anti-DDoS measures, but this is on every query with that many tags, even if it's the only search I've performed that day.