I'm sorry, I didn't mean to offend – I'm rather tone-deaf, especially in foreign languages.

The problem with iD is, that it's the only editor that adapted the *unapproved* (and inactive) proposal to use 'crossing=marked'. So what those developers do is basically fueling an edit war, by calling the approved tagging outdated and enabling iD users to act out the opinion of the iD devs through what would be considered an automated edit, in any other case. 

This is not OK, and neither JOSM, nor Vespucci suggest such semi-automated edits by themselves. They stick to the approved tagging scheme from the wiki. The french language version of the wiki[1] doesn't even recognize the 'marked' variant. And whatever reason for introduction, it has become obsolete with the approval of the 'crossing:markings' key.

Changing the approved tag 'uncontrolled' to the unapproved 'marked' just because iD lies about the status, is quite offensive to all the users that stick to the wiki. In any other case this would be considered trolling, however in this case the trolls are the iD devs. Please, don't play their game. That doesn't improve the map data.

Just because iD "warns" about something frantically it doesn't mean that something is actually wrong. And sometimes the suggested fixes don't improve anything; in worse cases they just mask errors, which makes it near to impossible to identify them.

So map with purpose and don't get distracted. iD is just a tool, and not a reference for good mapping practices. ;-)

[1] https://wiki.openstreetmap.org/wiki/FR:Key:crossing