Software ecosystems with more than 2 platforms that need to be supported by developers just never happen.

Look at the desktop - we have Windows and Mac (and for a while it looked like we'd lose the Mac), Linux is still a desktop also-ran.

Look at the web - it took Microsoft completely neglecting IE for 5 years before there was any momentum at all towards other browsers. And now we're back to web developers mostly neglecting Firefox and praying for the day they can drop Safari support so we're 100% Chrome.