I’m fixing some of the many errors that are around my area, made by other people on OSM, with reports from KeepRight!.
One error are regarding “key:abutters”

For example: on

This way uses deprecated tag abutters=residential. Please use landuse=* around the general area and abutters=* along street-front exceptions. instead!

What does this mean and what should I do to correct it.
Key:abutters and key:landuse are both keys that should be used on nodes or areas, not ways. Has this changed since someone was doing this maybe?

Should I keep landuse=residential on the area that the residential are and delete key:abutters=residential on the way?

The problem is that I can’t see the difference between key:landuse and key:abutters. They are both used on nodes or areas and contains the same information.

“abutters” is not deprecated. There was some attempt in the past to deprecate it by people who did not understand why it can be useful.
As it is specified on the wiki, “abutters” applies to ways only (where landuse applies to areas normally). “abutters” can be used where you cannot draw polygons because you don’t have detailed satellite imagery in your surveyed area.
I think keepright is reporting abutters as deprecated because someone putted it in this wiki page:
which is something I can fix.

And here is what KeepRight says about “deprecated tags”:
As shown in some tags get replaced by others as new tagging conventions evolve. Consider this as a notice, not as an error. The term ‘deprecated’ is deprecated; you’re free to tag anything the way you like. This is just a hint for new tagging conventions that have evolved in the meantime.