VPN is not mutually exclusive with using SSH. What he's saying is that people should firewall their SSH ports to only allow access from trusted IPs, and VPN's make that easier to do.
It's not really about one being more secure than the other. They are both very secure. It's just good to have multiple layers of protection in case something goes wrong somewhere, whether it's caused by human error or something else.
Yes, in a sense those things are mutually exclusive.
You can get in a network by VPN or SSH. Yes, after that you can also log into a computer by SSH, but the question remains - why access the network by VPN instead of SSH?