It's ok, I posted that because it's a really common practice to market things like universal and when you visit the webpage it's just for iOS/Mac. I would gladly buy it if you release this for Android/WatchOS if it fits my needs.
Honestly, your initial comment comes off as whiny and entitled: you lost maybe 30 seconds of your time clicking through to something that wasn't relevant to you, and there's "no excuse" for leaving a drive-by comment attacking the author for their choice of tech stack for a side project just because of that tiny inconvenience.