Sorry to rock the boat. I'm sure whichever WMF teams made these websites (https://api.wikimedia.org, https://developer.wikimedia.org) likes them and has their reasons for having made them.
But does it make sense to have a bunch of technical stuff (api.wikimedia.org, developer.wikimedia.org) that isn't on mediawiki.org?
The downsides in my view are...
- duplication
- de-centralization (less viewers, less editors, more pages getting out of date)
- barriers to editing (developer.wikimedia.org in particular because it isn't a wiki)
- technical debt
- inability to translate
Areas where I see duplication...
- https://api.wikimedia.org/ appears to duplicate https://www.mediawiki.org/wiki/API
- https://developer.wikimedia.org/ appears to duplicate https://www.mediawiki.org/wiki/MediaWiki and https://www.mediawiki.org/wiki/New_Developers