RVs went long way since I start using them.
Started with 20' ClassC and when my family expanded and grow up, ended with 40' bus. In the mean time I had one DP who was wide body. You might say that 8" extra width is not much, but it really made the motorhome much more spacious.
Now the slides were invented about 20 years ago.
The first generation was adding +- 18", but last year on campground a neighbor invited us to new TT.
It wasn't long trailer at all, but thanks to opposite slides in the rear, they had huge living room, kitchen island, working fireplace on Central wall HOLY ****- lot of people don't have half of that in stick house.