This is bad and evil because gadgets writer are often less experienced as the MediaWiki-Developers are. Furthermore the code is often not double-checked like the MediaWiki-one.

Moving the gadgets to another tab could raise the impression that activating is save. But often Gadgets suffer from substantial security vulnerability, so fooling the user.

But why we have Gadgets? Simple answer: Because MediaWiki is insufficient for lots of cases.

Irony? Evaluate yourself.

Marking WONTFIX per concerns raised by Rainer in comment #1.

Gadgets are created by the community. Although great things have been created through that system, they are still not as safe or stable as native functionality that has been through extensive cross-browser testing, code review and security checks. And as such they should not be promoted mixed without the ability to distinguish them.

The Gadgets extension already has the feature of "categories", so one can have a category "Edit gadgets" (instead of adding it to the native "Editing" tab.

If something created as a gadget turns out to be suited as something that would belong in another tab and is stable enough to be as such, then I think the proper procedure is to have it be part of core MediaWiki or an extension. - in order words, request the feature in BugZilla and link to the gadget resources as "patch".

Gadgets are kind of a labs environment, once it's grown stable and useful enough for general MediaWiki use (not just Wikimedia wikis), then they are probably suited to become part of core.

For example, ajax watching has been in core for a while now. If I recall correctly that once was a gadget.