You can still buy datacenter edition, and some of us are forced to do so, if we wish to continue to use Jira and Confluence. For us it's not a problem, we're heavily invested in the Atlassian suite of product, and sell consulting, so we get a significant discount. For some of our clients it's a massive problem, as Atlassian cannot promise them that data won't leave the country, if fact it's certain that it will, because there's no AWS datacenter within our borders.
Atlassian completely ignored the large number of smaller customers who are legally forced to use an on-premise solution. If the software industry was so hell-bent on SaaS there would be a great business oppotunity in creating an on-premise Jira competitor.
It is not a "contact us" pricing plan. The Data Center prices are publicly available on their website. It is more than twice as expensive as the Server offering, but still substantially cheaper than Cloud for the same number of users.
And it is the exact same software as Server with some extras enabled like support for multiple nodes, so upgrading to it is as simple as pasting in a new product key.
