> Isn't this a massive copyright infringement on Apple's design?

I'm not a lawyer but I think Xerox had the same question back in '89 [1]. Given Apple's luck in pursuing infringement claims against Microsoft [2], I doubt a copyright suit would be fruitful in this case.

[1] https://www.nytimes.com/1989/12/15/business/company-news-xer...

[2] https://legal.thomsonreuters.com/blog/1988-apple-sues-micros...