I thin that iD wants to change "access=public" to "access=yes".  Actually, the bigger issue here (which predates your edits) is whether https://www.openstreetmap.org/way/212292004 allows bicycle and horse access or just foot.  If it is just foot (and I'm guessing that it might be because https://map.atownsend.org.uk/maps/map/map.html#17/54.14227/-1.51437/O/P suggests that there's an unmapped "public footpath" down here) then "highway=footway" is probably the better tag for way 212292004.  If it does allow bicycle or horse access, then it's probably best to add explicit "bicycle" and "horse" tags too.
Cheers, 
Andy
PS: Any other questions just ask.
