I don't see why anyone would pay more than $10/mo for a non-Gmail email service. But I'm also a grumpy weirdo who prefers to use plain-text email wherever possi

I don't see why anyone would pay more than $10/mo for a non-Gmail email service. But I'm also a grumpy weirdo who prefers to use plain-text email wherever possible, so all these "Gmail-killers" don't really offer what I want.