Splitting 404s by spider

I have 404s coming into Sentry, but I’m not really interested in 404s triggered by spiders; I only want to capture 404s created by genuine users. I created a tag called “bot” that differentiates between bots and users. Then I created a server-side fingerprint rule to split the 404s by spider/user.

error.type:Symfony\Component\HttpKernel\Exception\NotFoundHttpException -> 404, {{ tags.bot }}

However, nothing has changed. 404s still come in using the default grouping (grouped by exception stacktrace, in-app exception stacktrace). What am I doing wrong?