Because of the OSM data model, changes can't be really held in "unaccepted" state. One would run into editing conflicts[1].

On Wikipedia withholding edits until review works in some language versions [2], but because Wikipedia pages are "atoms" that stand on their own, they have it easier.

[1] https://learnosm.org/en/josm/josm-conflict-resolution/

[2] https://en.wikipedia.org/wiki/Wikipedia:Flagged_revisions/Si...