People matching the <(People) filter>
Events matching the <Events filter>
Places matching the <(Places) filter>
Repositories matching the <(Repositories) filter>
Media objects matching the <(Media) filter>
Notes matching the <(Notes) filter>
All the filters listed above effectively do nothing, or am I mistaken ? I think they are core features, so there may be a good reason to have them. Perhaps as an illustration of how to write a filter.
For example, I often use a 2 stage filter. The first filter to select the lines that I want, and the second filter to add spouses of everyone in the first filter. So the second filter has just 2 rules:
people matching <filter>
spouses of <filter> match