Linus Torvalds didn't conceive much of anything. He hijacked the UNIX code framework especially the patents and IBM let him get away with it.
take something and make it useful to everyone.
Everyone being the entire world, without having to pay anyone in the US for using it, of course.
Incorrect. He created a POSIX-compliant kernel based on the Minix (a student-oriented teaching kernel) kernel. The only thing Linux and UNIX have in common is POSIX-compliancy.
IBM didn't develop Unix, AT&T did, originally. Not sure why you think IBM would have a dog in that fight. There is IBM tech in the kernel; IBM put it there.
The whole "Linux infringes Unix patents" was already litigated in the SCO case. SCO got their clock cleaned in that one. It's a non-starter.