I’ve been having all sorts of issues with the Mac client for the past month or so. A lot of lag that seems to be server lag (since my connection generally seems fine with everything else), along with inability to contact the login server, coherent host crashes, etc.
About a week ago the game stopped opening altogether (it would “open” but never actually come up on my screen, no matter how many times I tried, or how long I waited). I found that step four here https://forum-en.gw2archive.eu/forum/support/support/MAC-Basic-Beta-Client-Troubleshooting helped to solve that issue (I renamed the file, rather than deleting it, but a new one was created on launch all the same), and the game played fine after that for probably two or three days before the process seems to have restarted again (lag → “unable to contact the login server” → coherent host crash → game reluctant/unwilling to open/log in).
No idea why this helped, especially since it seems to have only worked temporarily, but it might be worth a try if you’ve not attempted it yet, because it did get my client to open again, at least.
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