no, it's not.
I'm not talking about app programming shops, or the graphic design places, where OSx is still leader.
I'm talkign about Banks, Corporations, conglomerates. Financial institutions, and just about the very foundation that modern digital era runs on.
it runs on windows and it runs on n*x. its almost entirely x86 and PowerPC.
Apple has done a fantastic job at convincing everyone through media sponsorship, product placement and student value that Apple is prolific everywhere, but it is not.
https://www.netmarketshare.com/operating-system-market-share.aspx?qprid=10&qpcustomd=0
and this is only for desktops.
this doesn't include servers which are 99% x86/PowerPC, since there are no modern Apple servers or server OS.