I just returned from a month in Europe where I was able to observe just about every type of luggage style and combination in use. You know what? It worked for most people. There were the minimalist carry on only. There were the larger "check' bag sized bags. There were the backpackers. There were the Sherpa husbands single-handedly trying to manage a car load of luggage.
My point is, that as long as people can manage their luggage, why worry what they have packed and how they have packed it? I imagine that we all have our preferences in various situations. Even the Sherpa Husbands, (who do get a little annoying if they block access to the train) seem to find ways to manage that work for them.
This trip I brought a little bit more than I usually do since I wanted to have covid supplies available. I ended up with a checked bag and a carry on bag (backpack style) that contained enough essentials that if the checked bag were misrouted I would be fine. My checked bag made every flight.
I don't think anyone will disagree that when one has less luggage it makes transfers between locations a bit easier. However, that doesn't mean that people choosing to pack differently are packing "wrong." I think we sometimes forget that here.