Allow to add information about a bar or supermarket cant destroy the whole map.
Forbiding to edit the streets is an option to prevent vandalism.
But forbiding everything can not be a solution to this problem.
Evereyone has to register just for adding a … water hydrant.
I think this is a to high level for some persons to shaire their knowledge about a local area.
Being able to contact other mappers is an important part of OpenStreetMap - we are a community. Of course you can always avoid being contacted by ignoring your mails but at least there is a chance of being contacted when having an registered account.
There is no technical infrastructure for allowing only certain types of edits depending on your account status. The server doesn’t even know what a tag means, so it has no idea what a “supermarket” or a “street” is. All semantic interpretation is done on the client side, i.e. in editors and applications.
I understand that low barriers to contribution are generally desirable, although it should be noted that understanding a feature-complete OSM editor is quite a high barrier even without any account creation involved. That’s why we have specialized tools for low-barrier contributions: For example, you can report errors along the lines of “there’s a fire hydrant missing here” on OpenStreetBugs without creating an account. (It is planned to integrate this feature into osm.org.) There is also the possibility of editing special-interest maps such as wheelmap.org without an account.
Of course it is possible to avoid attempts by the community to contact you, but not including an explicit option for this makes it clear that we would prefer if you didn’t do that. If someone has done this in the past, it means that their contributions will be deleted within a few weeks or so because we cannot inform them about the license change.