Simply put, no. The AKV is a globally known resource. Everyone knows what it is, where it is and how to get to it. It's the same for everyone. The SCS is different for everyone. Its location on the internet is known only to your enterprise and no one else. And even if someone does learn the location of your SCS, a firewall blocks all IP addresses to it except yours. What's more, only callers with the correct digital certificate (one that's regularly changing) can access the SCS (no usernames, no passwords, no tokens). By comparison, the AKV is a gigantic honeypot eyed by every hacker on the planet and accessible by users with a username and a password. While the AKV keeps private keys accessible indefinitely, the SCS allows access to its private keys for only 1 day - after that they're destroyed. And during that 1 day the private keys are accessible only by the heavily secured GGC agents. Finally, and most critically - unlike the AKV, enterprise IT staff never have access to private keys on the SCS.
While Microsoft is indeed a great company with great security, it has so many balls in the air that it is constantly struggling to secure its own systems (see "Russia hacks Microsoft: It's worse than you think"). Microsoft must be everything to everyone while AutoCert does just one thing - keeping the keys to your kingdom absolutely safe and unhackable.