I just got very shiny eyes when hearing the (hidden/poorly documented) exclusion filters worked again but then my eyes lost their luster again… They are now kind of working for me: Of the two examples leafo gave, the result number one returns the same as an entirely unfiltered list would. The second example works though. My guess would be that users now have to add tags before they can exclude them.
Nevertheless: Thank you Minoh Workshop! You have improved my itch.io experience - and with a little luck, that of others. :)