It seems that Bitbucket and GitHub are trying to emulate GitLab’s strategy of being a one-stop tool rather than just version control.
Jira may be the most comprehensive issue tracker (which isn't necessarily attractive -- but then they have Trello now, too), but on the version control and CI front I don't think Atlassian will have an easy time competing against Azure/GitHub/GitLab.
The common user just realized he or she needed more and demanded them for free.
The Enterprise market had DevOps features long before DevOps as term existed.