MediaWiki CMS is a special CMS in the sense that all its “management” pages are not hidden from any user. This may cause UX as well as information security problems.
To me it causes an SEO problem because then the hundreds or easily thousands or tens of thousands or more of pages are being crawled (they will be crawled even if not indexed) and it takes crawling power from my already weakly-crawled website.
My MediaWiki website is all core.
I expect my readers to only read article pages and category pages.
I don’t recall ever finding a URL of an article page or of a category page to contain URL parameters.
As management pages tend to have URL parameters, I thought to put the following command in robots.txt
Disallow: /index.php?
Is that a problem?