I almost agree; the principle is right. I used to have my email address on my own domain, but was forced* to relinquish my domain and so switched to a gmail address as my primary address quite a few years ago now. So for me gmail outlasted my own domain, even though my domain was under my control. And I suspect for the majority of people this would be the case too. Make your primary email address a Hotmail, Gmail or Yahoo one and it is very unlikely to go away and is probably more effectively permanent than your own domain (I still have a pre-Yahoo Rocketmail.com email address that still works, even though I might only log into it every other year).

* I remember thinking it's only ~$20 every two years to renew, how can you not afford that? Well... let's just say there is no way you can predict the ups and downs of the future.