In my case, Bitbucket will lose someone who was just using it as a dumb git storage backend, and did not engage with the Atlassian products at all. I assume that they won't be particularly bothered to see the likes of me drop off.
This is exactly how I see it too.
If anything this move might be beneficial for Bitbucket because if there's a 0% chance we would use their other paid products, we were just taking up resources.
Bitbucket’s killer feature is integration with JIRA and the rest of the Atlassian stack, so I doubt it’ll have much impact.
I guess that depends on your definition of “killer”, particularly wrt Jira.
Free private repos is exactly why I was using BitBucket. I will have to think it moving will justify the effort.