https://www.youtube.com/watch?v=pwVs6-Ns2N0

I have a similar situation and plan on doing this to repair my couch. It can't look worse than it does now. :(

The cats did not stop scratching the couches until I gave them desirable places to scratch. You can't just toss up a carpet covered post in a corner and expect them to leave your furniture alone. I have never, ever seen a cat use one of those stereotypical carpet covered posts on a carpet covered square.

Cats usually fall into one of two types of scratchers--horizontal and vertical. I am "lucky" enough to have one of each. So, observe your cats and see how they like to scratch. If you're not sure, try out some different things.

In addition to having preferences for how they scratch, cats have preferences about what they scratch. The cat who prefers to scratch vertically loves scratching cardboard. The one who likes to scratch horizontally prefers sisal rope. Both will occasionally give a good scratch to low pile carpet. The horizontal cat also prefers an elevated surface--so we got him a thing that's shaped like a sideways S like this one and the vertical scratcher gets a slightly nicer version of this around the house. I also have a few of these and one of these. I put catnip on all of these things at least once a month. They all get used pretty frequently, and anything that gets too ratty is replaced, because they won't use it if it gets all scrotty.

In addition to these things scattered around the house (it seems like a lot, but it's really not) we have a cat tree in the corner of the living room. The cat tree has sisal posts, and they both love to scratch on those. They also love having a perch in the house, and being able to have that spot reduces their anxiety (and need to neurotically scratch).

It's more stuff in the house, it's more to clean, and it's more to pick up when guests come over. But, since we've done this, the couches have not picked up any more damage. I know you'll feel like a crazy cat person, but when we take an animal into our homes, we have a responsibility to provide for them, and if they are scratching your couches, they aren't getting everything that they need.