It's probably splitting hairs, especially outside the tech field but "Linux" refers primarily to a particular type of kernel. A ton of open source software gets packaged with that kernel, - a lot of which you'll also find on UNIX and other UNIX-like systems. In that sense there is a degree of similarity between macOS and Linux. However, macOS doesn't borrow much if anything from the Linux kernel, which is the part the Linus developed.

macOS and iOS both have a Darwin kernel that is based on Mach and the architecture of that kernel is quite a bit different than Linux.

Totally agree though that a lot of peoples' interactions with the world of the Internet and many "Smart" devices depend on Linux.

Linus did also create git to help maintain Linux and it is a wildly popular version control system.