See also Bug 5835 where the feature was originally requested the way it is, but similar complaints were raised there as well.

Also we may want another field to select a namespace when this "Pattern" field is used.

This was vastly improved by @thiemowmde in 0943f81e9582aa9a6a0ca70be1433bc914c0ca3a where the field name now explicitely says "SQL LIKE pattern (e.g. %)".

I wonder if the page name should be normalised according to MW title conventions. E.g. if there are pages "Spam_1" and "Spam_2" (rc_title conventions) and you enter "spam %" you will find nothing because: 1. you have to enter an uppercase "S" and 2. you have to use "_" instead of spaces. Either it should be warned/documented either the title pattern should be normalised to rc_title, taking care not to double-encode the "%" and taking care about $wgCapitalLinks and $wgCapitalLinkOverrides.

Change #1118002 had a related patch set uploaded (by MolecularPilot; author: MolecularPilot):

[mediawiki/extensions/Nuke@master] [WIP] Add regex filtering option to Special:Nuke

https://gerrit.wikimedia.org/r/1118002