[brk]

Some of them do have vents in the lid, which works for personal carry-home in your car. But for delivery, the driver usually has 3 or 4 pies at a minimum, in an insulated bag, so nowhere for the steam to go.

The obvious solution is a pizza oven on a vehicle chassis, where the pie is cooked en-route and delivered to you literally as it comes out of the oven.

[contingencies]

Zume (died) tried that and Wonder (fleet of 500 vehicles) just ~failed ("Layoffs. Phasing out trucks. Searching for cost-efficient operating model."). Stellar Pizza (2-3 vehicles or so) is apparently still trying, their capex seems to be around ~$250K/unit.