It is, especially when you consider economies of scale with things like computer production.
Building 50 boards is expensive. Building 500 is cheaper. Building 5 million? That's now custom equipment dedicated to the project, and costs just plummet per unit.
I also like the Pi4 model in which the "higher end" versions seem to be more profitable, subsidizing the lower cost/RAM models.
There is really no competitor that has even been a consideration for us. Software stack is the hardest to get right with them at scale for fleet management IMO.
Well except the people living around the place where the raw materials are extracted, but that's another story.
I think the RPi's attraction for commercial users is less the price point and more the size of the community around it. It's by far the most approachable system to work with when you need a small linux device with cameras and gpio.