I really like the UI - is this an Electron app, or what is the stack you use?
And sure enough Mac users account for 30% for the revenue today.
Another advantage is that it runs completely on the user's computer. So I have no database or back-end to maintain. There is only a small server to generate licenses + handle some analytics the app emits both built on ASP.NET. The only data I store is in a Microsoft Azure table. I pay around $2 a month for all azure costs.
So basically a license is public info, the app enforces that the logged in user must match the user in the license.