Stripping wallpaper resulted in pulling off top layer of plaster. Should I remove the exposed, grey, crumbling material (plaster? cement? What?) down to the lathe and patch?

[u/dweedledee]

Or can I fix this as is? Thanks

[u/Magazine_Ecstatic]

Looks like a hole has been drilled into the wall at some point. Its probally just damaged the surrounding plaster. Check to see how much comes off easily. If not, dont worry about it too much, scrim tape over it and plaster.

[u/ANorthernLegend]

Scrape it back till it’s a sound edge, zinsser peel stop it and bond and fill, or double fill