Bar Soap
Bar soap is truly a thing of the past. It's slippery to hold and makes a mess on the tray. Boomers often buy bar soap since they're just sticking with what they know, but they may be onto something with how much less plastic waste is involved.
Transition Lenses
Having transition lenses is very much a 6-year-old thing and a Boomer thing. There's no in-between. To be fair, they're pretty helpful, especially for folks who have a hard time keeping track of objects (Boomers and 6-year-olds.) These lenses fade into a nice, UV-protective shade once in the sunlight. They have a bad rap, but they're useful.