The alternative to such dictatorship over own content could be buying own domain and running own mail server. However, most people won't run such system, nor would they accept implied costs.
Or you can buy your own domain, and have an email service provider, of which gmail is a mostly free (cost wise) one, host it. I recently switched from running my own mail server to using gmail, and it was simple.
The idea of using "twitter style" (guh!) @some.name addresses loses a lot of functionality, like throw away or customized addresses, that perhaps many people don't use (but more people should). Plus, what importance does the @ have to do with this scheme? Just use some.name. One advantage of hierarchical email system, of user@domain, is that there isn't a landrush to get exclusive access to the user portion of the name. Two people named Joe can exist at different domains without conflict.