I need a large suitcase (25" that is totally full) for a week long trip, there's no way I could carryon everything, especially with the 1 carryon rule. Especially on a trip like last month when we had to take jeans and sweatshirts. We buy alot of stuff at WDW too, I need a bag just for that.
We had a full plane on our trip to FL last month and they were having a hard time stuffing all those wheeled carryons into the overheads. I carryon my laptop and a small bag that fits under the seat (and put my purse inside because of the new rules).
It did sound like the screening machine will be put in the baggage sorting system by Spring, so maybe curbside will come back then. One good thing is that your bags will be screened in front of you.