The only computer that is invulnerable is one that is on its own power supply, in a secure structure, on no network.
That’s a fact.
But, that said, the Mac OS is pretty secure for the most part.
LOL. . . no, better yet, turn it OFF.
And you're right. The Mac has been and is pretty secure. It has been the target of orchestrated specific hacks at Black Hat conferences using prepared scripts through vulnerabilities requiring the user to take a specific action, usually downloading and executing a file. The weaponizing of these vulnerabilities can only be accomplished by converting the file into a TROJAN horse application, and then using social engineering to trick users into doing the downloading, installing, and running the malware. No successful self-replicating, self-transmitting, self-installing, self-running application has ever been seen for Mac OSX. Seven candidates using various vectors have been presented over the past twelve years. All failed to work. The only successful malware for Macs have been those Trojans. . . and Apple has addressed that problem.