They are supported, they have more limited functionality as “most” users are using mobile apps.

what problem do you have?

Sonos has data on how much usage each controller gets.  They used this data to concentrate resources on where they will impact the most users.  Unfortunately, the data pointed to the PC/Mac controllers as the odd men out. 

Setup and admin tasks are only available on the iOS/Android controllers, in part because that’s what the vast majority use, but also because laptops are less likely to have NFC/etc and be convenient to wave about for Trueplay tuning. As for desktops, well, I rest my case.

Every day, I use my controller on my Mac. I’m using it right now. It has support, every time they release a new version, I update it.

However, as previously discussed, you can’t set up “new” speakers or do admin processes with it. It’s absolutely fine for controlling already set up devices. 

same here, I am using the Sonos Controller on my MacBooks and Mac mini and it works fine - apart from the setup and admin processes I feel comfortable to use it and receive regular updates