A mail server is hard. Writing applications is hard. Designing a website is hard. Professional work is hard. But setting up your initial mail server is not hard. Read some guides (ahem: https://flurdy.com/docs/postfix ), fix a lot of typos, and you're up an running. Same with developing the initial version of an application, or designing the first draft. Not rocket science. Not easy but not that hard for an experienc…
It's a consumer-oriented SaaS for taking control of your personal mail - there is no enterprise pricing, nor even a subscription pricing option - though you can you can choose to pre-pay for the service years in advance.
Kopi uses Amazon SES for email delivery. We know Amazon wants to make sure that their service is a viable product for mail delivery at the commercial enterprise level. The idea is that Kopi can survive as a viable retail product by riding on the coat-tails of that desire and arbitraging the cost of mail handling via SES so it's cost-effective at consumer level.
The intention is to run it as cheaply as I can, ($1USD / month at the moment, though I make no guarantee that it can stay that cheap forever) and to give people the ability to choose between different mail services.
The idea is that you can manage your own domain, and setup your DNS to use Kopi as your mail exchange via DNS MX records to forward your email to whatever mail service you choose to use. If people don't want to even run their own domain, they can can use the shared Kopi domains if they want - with the understanding that those mail addresses are locked to the Kopi service, but at least they can change mail service whenever they want.
The goal is to be easy enough to use that you can set up your email handling via a smart phone, and cheap enough that running your own email handling using free software should seem expensive by comparison.
Though I'll admit - marketing this thing is a bit of a problem right now :)