He did indeed partially hit it, but in a different way than you think. His first point first was free, the second was speedy. If you would be able to check a bag for free and you got it back within minutes of arriving at the carrousel, you'd probably check bags more often than you do now already. I posit a third point: if the likelyhood of bags going missing or being pillaged by TSA (I think baggage handlers are more trustworthy to be honest) is reduced to zero, even more hesitation would be gone.

But in reality, for leisure travellers, only the 'free' part is really of importance. They don't care if they have to wait a bit and in the pillaging thing really isn't all that frequent (it's never happened to me), but those extra few dollars really make a difference in people's willingness to check their bags. If stuffing it all in a carryon allows people to save $15, they will!

Which is why we in Europe (I love starting sentences with this) don't really have this problem of people bringing in the kitchen sink to stick in the overhead bins: Only LCCs charge for checked baggage and in those cases it's mostly accepted (and I believe thus often paid, though it must be said I avoid LCCs like the plague) because 'well, it's low-cost so that is to be expected'. Not so of full-service carriers; if KL started to charge a baggage fee (beyond the first bag), I'm positive the exact same would happen.