Inflation is by definition the change in prices of a general basket of goods. Some things will outrun the basket and some things will underrun it. In general consumer durables have underrun, things like TVs and yes, sofas, are way way cheaper now than ever before. I'm not really sure why you would exclude IKEA type furniture, in most cases it's probably as good or better than a really old hand crafted one. If back then you needed to get an ultra luxury sofa but now you can get an IKEA one for the same general quality then that's a massive win for affordability even if the ultra luxury category still exists.