TYPO3 Core

Thanks for the praise, much appreciated.

The referred extension seems to be actively maintained, did you already bring this up there? The code doesn't look too different than what a core feature might use. The sitemaps though would need caching, but that should not be hard to implement.

If there are fitting extensions out there and there's no immediate need to put something into the core, we try to support a healthy and active extensions ecosystem.

I would kindly ask you to try to get in touch with the extension author(s), if we can help out (or you think this is a mistake), let us know!