Yes I also grew up with my parents saying settee, but I’ve called them sofas for many years now, mostly as when we have gone to replace one, online and in the stores they are known as sofas
My granny used to have a couch. I haven’t heard the word for years, except for psychiatrist’s couch. We have an item in the sitting room which we bought as a bed- settee. It is now a sofa- bed, I suppose.
I am going to be an unashamed couch-potato (feet up on the sofa) with my Kindle, for the rest of the afternoon, after 48 hours at dd’s, helping with 3 very little Gdcs. Bliss!