It always is. I could kind of see them releasing a 64-bit version of Monkey in some ways, as there are products people can still buy new that use Monkey, however, from what I've heard for Line 6 folks, it would be a pretty monumental task just because of the way Monkey is written and all the legacy connections.
The thing is that Macs are still represent a minority of the computers out there, and even for a music-oriented company like Line 6, a minority of their users are on Macs. So you have a small sliver of their overall user base who are affected by the lack of 64-bit support for these applications, and it's not like adding it opens up additional revenue streams for them. It would be a nice thing to do, for sure, but unfortunately, I don't think that's enough justification for them.