On the other hand, I find the integration between Atlassian tools to be pretty barebones. It feels very clear to me that Atlassian tools are really developed separately, with a separate jira task to integrate specific parts. There's no "coherency" to them.

You are right that it's difficult to replace the entire Atlassian suite. The thing about Atlassian is that when there's if there's a box to check on a feature list, they've made sure to check it. If you go around the office asking everyone what features they want, Atlassian is going to check all those boxes. That's pretty hard to compete with.

> It's not just issue tracking, but alerting, issue management ITSM tools, source control, CI/CD, release management, documentation and I don't know what else that all need talk to each other and provide traceability from any point to another.

Isn't Phabricator trying to do all of this? It seems to get quite a lot of fairly high-profile usage in both enterprise and community-focused/FLOSS contexts.

Well, to add a counterpoint, never in my career I have encountered a place with a proper atlassian products integration. The most common integration I saw was using Jira and Confluence, which seems a little underwhelming to me. In all the places I have seen a mishmash of different products not really glued together and the workers had to navigate that mess. One of the places I’ve worked on had salesforce for customer sided issue tracking, and JIRA for software development tracking. Support engineers had to copy and paste tickets to raise defects and bugs, keeping track of all the interactions in both systems. Silly stuff.

I don't think I've ever seen integration between confluence and jira that mattered.