Larry, thanks for trying to save me the effort, but in this case it was a misfire. 😉
This problem is different than just general slow performance while loading Steam and some games. This is a bona fide bug on our part. Unfortunately, it's intermittent and seems to be happening much more often for some of our users then it does for us in testing. In other words, I have seen this happen, but only relatively rarely.
We still don't know why it's happening. Under the hood, what's happening is that the wineloader process for Steam is communicating with the wineserver process. For some reason, they are in a tight loop where one makes a request, the other responds, and then the request (or another like it) is immediately made again. There's apparently no real work happening here, they are just in a "What's mine say?" "Dude! What's mine say?" "Sweet! What's mine say?" ... screaming match. Eventually the do break out of the loop and then resume doing real work. It seems to be a timing thing.
It's on our radar, but due to the uncertainty, I can't promise when we'll have a fix. Hopefully, it will be fixed by the jump in Wine versions that will be part of our 7.0 release.