I agree with the comments around organizational alignment. The further 2 people are from each other within the hierarchy, the less likely they are to understand each other's role. I think this has to do with the metrics our managers place on our work. If we share the same manager or senior manager then our goals should be similar. If we have to go up multiple chains of command before we share a common manager then our goals will be very different.

If the primary metric a DBA is measured on is availability then how does that align with a developer whose primary metric is delivering user requirements on time?

I have seen very little tension between developers and DBAs at my different jobs. I am typically happy to speak with somebody who comes close to understanding my issues. As a developer perhaps I don't hear the grumblings from DBAs in their circles. If I have issues with my business partners I try to let them know in as civilized way as possible. We typically do lessons learned meetings after large projects with our business analyst, project managers and technology partners to help improve our overall process.