@Aklapper https://en.wikipedia.org/wiki/Wikipedia:Edit_filter , and answer your second question, No because I am uncomfortable actually working in code hence why i've been heavily working in L18n and documentation.
Edit: Typo fixing

Thank you @Aklapper

Although on the English Wikipedia we rely on MusikAnimal's Stale Filter Report, something like this could be quite useful.

@Samtar We probably should get this or atleast try to get this out there within the next few MW releases?

This should be configured on a per-filter basis. E.g., when I write my filter, I can tell it to automatically disable if there are no hits after N number of days. An across the board auto-disable may not be desirable, as many filters are for long-term abuse and are intentionally left enabled despite the lack of hits.

In T142656#2699557, @Zppix wrote:

@Samtar We probably should get this or atleast try to get this out there within the next few MW releases?

Let's try to get some input from other edit filter managers and scope out the requirements. This is sort of a big feature and will require database changes, I believe. I'm interested in helping out but can't commit to anything right now.

@MusikAnimal is this the sort of task which can be added to the Community Wishlist?

@Samtar: See https://meta.wikimedia.org/wiki/2016_Community_Wishlist_Survey for eligibility

Agreed that this should be on a per-filter basis. Automatically disabling filters from serverside just because they are staled is a complete WONTFIX, apart from being not that easy to code.

Now that the abuse_filter_log view is no longer replicated (T375751), I'm wondering if a "Stale filters" report like my bot did would be something that could AbuseFilter could provide for us? I envision either a Special page for this with data similar to the bot report, or even a new search option at Special:AbuseFilter such as "Hide filters that have had hits in the past N days", where N can be an interface message so that each wiki can configure their own definition of active vs stale filters.

Does this sound at all feasible?

In T142656#10392308, @MusikAnimal wrote:

I envision either a Special page for this with data similar to the bot report

See T193064: Create a dedicated page for stats.

I suggest that this task is closed as declined or invalid the way it is currently written. There are filters that are not meant to match things often, precisely because what they aim to find happens very rarely. It is not necessarily a performance problem, or a problem at all, assuming that the filter works correctly. What we need is things like T93564 so that we can easily find filters that rarely match anything and can check if they work properly and are needed.

@Nirmos note that even if a filter is not activated often (meaning not all of its conditions are met often), it will still be run every time up to the point where its logic doesn't match the action, therefore there can indeed be a performance issue.