Also, the pipe below this is still very solid. I temporarily blocked off the hole to prevent sewer gas from escaping and the p-trap seems to be in good shape too.
I need to replace an old drain from a bathtub that was recently removed. I want to put a shower in its place. The drain is on slab and the home is from the 1950s. Once I took the old bathtub I noticed the rim of the old drain just crumpled to pieces. I’m attaching a photo of what it looks like...