It isn't just the barrier to entry, Microsoft famously paid the cost to enter the smartphone market. It is how many platform ecosystems a market can support pr

It isn't just the barrier to entry, Microsoft famously paid the cost to enter the smartphone market. It is how many platform ecosystems a market can support problem. Creating a platform ecosystem creates higher costs and lowers profits for everyone building in the market (the market in this case being "all smartphone users"). 1 more platform is going to be at least a 30% increase in dev costs (if not a full on 50% increase, and for large complex apps it can be even worse), and now if that platform gains market share, that is less sales on the other 2 platforms for anyone who doesn't support all three. So to make the same money as before, a company now needs to spend 30%-50% more on development expenses. There is a natural limit to the number of platforms that can exist when the cost of building across multiple platforms is non-trivial. This by the way was why even the tiny European market was able to support so many different 8-bit platforms back in the day. Porting costs were minimal, one or two people for a couple of months, and developer costs were much lower back then. Jump to the 90s and now suddenly you have just 2 consoles, and with Xbox losing market share year over year, we may soon be down to just one in another decade or so.