The problem here is that if you open “Issues” in iD over a town, you will be met with hundreds of error messages for Marked Crossings and Unmarked Crossings. It is difficult for a user to discover any other real issues, so this feature in iD becomes almost unusable. If we keep Crossing validation activated for Norway it will stay that way, and a lot of needed fixes will not be done.

If we deactivate validation, crossing:marked=* will still be a highly visible attributes for anyone editing those features in iD.

And keep in mind that we have no consensus on this tag in the community. It does not add any information on top of crossing=*.