I think the bigger question is if the robotaxi is a winner-takes-all market or not. It appears you think it's not. But some would argue it is.
It could be, but I don't believe that it necessarily will be. But more to the point for Tesla shareholders, I don't believe that we should want it to be a winner-take-all market.
Firstly, TN would become a regulated monopoly in many jurisdictions. Regulations would be brought to bear to limit just how far Tesla could go. Tesla could even face being broken up so that the entity that makes the vehicles cannot be the entity that owns and operates the fleet. How much Tesla could charge for fares and how much would be shared with private owners using TN could all be dictated by utility commissions. In short there is a whole pile of political problems here that we would do best not to step in, if we can avoid it.
Second, it would not be consistent with Tesla's mission. To accelerate the transition to sustainable energy and transport, We need genuine competition in this space. This has the potential to make battery packs 5 times more efficient reducing carbon emissions than their use in private auto ownership. So to get the biggest environmental impact from EVs, we need to maximize commercial fleet applications such as robotaxis. Competition will be the most effective way to speed robotaxis to market and to maximally displace less impactful private ownership. Service levels will be higher with competition and fares will be lower. This is truly the sort of thing the Tesla mission is to accelerate.
Third, competition allows there to be a much richer ecosystem, which can create lower cap, higher profit opportunities for Tesla. A lot of this emerging industry is destined to bond like rates of return on capital. But some parts of the supply chain will have much more dynamic, extraordinary returns. Already Tesla is willing to share the vehicle ownership piece with Tesla vehicle owners. Yes, that sells cars in the short run, but also in the long run Tesla owners are providing capital and earning modest rates of return on that capital. Tesla is able to grow the fleet larger and faster because it does not need to raise all that capital itself. Long-run owning a fleet of 12-year old rental vehicles is not a very exciting place to put Tesla's capital. But where Tesla could make extraordinary returns for rather low capital is in licensing the FSD software, providing FSD engineering services and manufacturing certain FSD components to other OEMs. That tech would all be optimized for the TN platform. So altogether you have a very strong ecosystem. Returning to the second point, this ecosystem can scale up much faster than Tesla can raise capital. So it can rapidly monetize the investment that Tesla is making into software, engineering and hardware (chips). Finally, the ecosystem will attract many other strong innovators to solve critical problems. For example, I love watching the Boston Dynamics videos. Maybe they could develop a robot that can service the rental cars, to vacuum, clean them and generally prep for riders. Could Tesla do this? Perhaps, but I think they've got bigger fish to fry at this point. Regardless, the sooner things like servicing the rental fleet gets optimized, the more quickly the robotaxi business can advance.
So as I've pointed out before, the robotaxi and other robofleet (i.e. semis) business is huge, potentially 25 million new vehicles per year and a fleet of 400 million vehicles. Tesla could be a nice regulated monopoly limited to operating a 10 million vehicle fleet at a 10% profit rate as a kind of public utility. Or it could be at the very center of a vast and dynamic ecosystem around a fleet of 400 million vehicles. Together that ecosystem could radically restructure the transportation and energy sectors to cut carbon emissions from oil by about 30% by 2030. So I don't want a winner-take-all market; I want full transformation.
