Macs designers are snowflakes on a world where Apple computers accounts for 10% of world market. Designers working on 90% of the rest of the world also need their tools.
Sketch did not invent anything, similar tools were already available on the 90's.
If industry you mean Web designers using Macs around Silicon Valley coffee shops then maybe you're right.
Having freelanced, contracted and worked at graphic design studios, ad agencies, font foundries, charities, finance companies, publishing companies and in government in the UK, I can safely say I've never seen any design departments use Windows as standard. None of these were in Silicon Valley and I've never worked in a coffee shop. This is also coming from someone who was almost religiously anti-Apple for many years.
You can certainly do good design on Windows, but there's no chance 90% of professional UI designers here are using Windows. And for user interface design Sketch is absolutelythe standard these days. I'd love to hear what similar tools were available in the 90s.
Sketch did not invent anything, similar tools were already available on the 90's.
If industry you mean Web designers using Macs around Silicon Valley coffee shops then maybe you're right.