Adding a new door to a house means that you must lock it, too. The more doors you have the greater the chance of a break-in, assuming someone wants to try.
The history of severe security issues with Adobe Flash is not encouraging for a new doorway into my Mac via the new Photoshop remote access feature. Useful? not for me, maybe for you, but any remote access feature introduces one more means for a security breach.
A properly secured system will not have a publicly accessible internet IP address, so a firewall will need to allow access through it to the required port(s), one more reason it’s not desirable as security goes (extra configuration with risk of error). As shown below, my working system is on a local LAN behind a firewall that hands out non-routable local IP addresses; it is not reachable from the internet except for ports explicitly allowed through the firewall (none).
Perhaps this is ultimately the main intention— enabling control of Photoshop for activities in a photo studio or similar, rather than from anywhere in the world.