Uh, have u flown Spirit? The most they'll allow without charging is 12 x 14 x 16 inches, or about the size of a rucksack. While I've been able to go to Costa Rica and Cancun for 4 days on that, it wasn't easy and may be even more difficult for some people. It's roughly half the capacity of the typical rolling bag that'll fit lengthwise in an overhead bin.

In addition to the Spirit trips, I've flown as an air courier to Asia 3 times, and that meant being limited to only the rolling bag for a trip of 2 weeks (they took your entire check-in allowance). Even the crew can and do carry more than that. So I'm a bit more experienced than most.

The problem is that there's very little consideration given for what might be reasonable or what the experience might be for the passenger in making these policies. It's all about added revenue and "what the market will bear" (even with resentment), so you get policies that can impact even those used to traveling light. The only thing to currently discipline the policies is passenger pushback, which is constrained by lack of competition in many places and driving not being a vaible alternative in most cases, either.

So it becomes a game of constantly pushing further...the REAL "slippery slope." Some kind of government regulation or mandated minimum could be inevitable because airlines just aren't gonna be reasonable on their own. Self-regulation won't work.