To a point where Microsoft should consider acquiring Atlassian because they are so similar in this regard

Nice, then how comes everyone and their grandparents are running Jira and MS Office? The latter across FAANG as well (maybe not the G with an in house competitor).

This is because both companies sell to the enterprise, not to the end users.

This is how Microsoft drove their phone business off the cliff: they built a product that their customers (corporate IT) loved but the users detested. When the iphone showed up Microsoft famously knew it was dumb because it addressed nothing that their customers cared about. But the workforce demanded change.

That's really not an indicator of quality. They lack competition. There is some correlation there but that's a different story.