For open source projects, but it appears to me that the enterprise projects are more BitBucket. This is just my experience, but I can't see how GitHub even competes with Enterprise Support that comes from BitBucket.
Hm perhaps. Without any knowledge or info whatsoever, I'd think that Bitbucket and Github are close for enterprise too just because of how big Github is. And then Bitbucket obviously has the experience and integrations that Atlassian provides to be competitive. Still feels like the edge would go to Github Enterprise in terms of popularity and revenue if I had to pick one.
I'm also partially basing this on Atlassian's public company market cap and revenue. I believe Atlassian does close to $65M a month in revenue (they did $58M/month in the quarter ending in June)[0]. GitHub I believe does around $15M/month in revenue nowadays[1][2]. They both lose some money. I actually believe around the same amount, $4-7M a month. Jira, Confluence, and potentially something else have to take the bulk of Atlassian's earnings.
Gitlab keeps raising money at pretty high valuations so I'm probably underestimating the industry as a whole anyway and missing some info.
Also none of this has anything to do with up or down time.