Not at $40 a seat. The public prefers no-cost assigned seating, but that's not on offer here. At today's price for assigned seats, I believe the public would prefer open seating for free.
They don't. I know many friends, coworkers, and acquaintances that say, somewhat boastfully, that they'll never fly Southwest because of Southwest's open seating policy. Yes, travelers would prefer no extra-cost assigned seating, but they'll put with paying extra for assigned seating because it's still better than open seating in their mind.