Maybe I am too dumb but the latest Google Earth Pro seems to be 64bit and I am running Wine 4.0 stable on MacOS 10.14.6 and if I start winbox.exe with "wine64" I get the following in Activity Monitor:
Screenshot Wine Winbox 64.png
So, that would not be enough in 10.15 ?
No, when you run it with wine64 you run the wine process itself in 64-bit, but it can still run 32-bit code from the Windows application you launched when run that way under Mojave if i'm not mistaken.
Under Catalina you need both the Wine process to be 64-bit (which is solved with wine64), and the Windows application itself too, which is the problem with Winbox but works well with applications that is actually fully 64-bit. I tried it with a 64-bit build of Notepad++ for example, and that works as expected under Wine on Catalina as long as I launch it with the wine64 command.
On some level I would also want a Mac native client, but if the iOS client is simply ported over with the help of Catalyst, it would probably mean that we would lack important features like having several windows with different functions on the same router open at the same time (which is one of the awsome features that makes Winbox soo good, even if it looks 90s-like
At the moment the iOS client is great for being a mobile client, but far from as good as Winbox is on the desktop, and it would need to become better before a desktop version of it would be able to replace Winbox on Mac for most of us.
So at the moment we simply really need to have a 64-bit build of Winbox, and at least to me it would only be a nice bonus if Mikrotik is actually working on making a good Mac native client in one or the other way.