I recall some time ago Battlenonsense did a deep dive into Apex's net code, and found the game's packets were exceeding MTU for almost the entire duration of the game.
So while increasing the tick rate is undoubtedly a trivial change, the associated factor of 3 increase in bandwidth usage will have dramatic negative consequences, unless of course there's also significant net code optimization to reduce redundant information being broadcast.
I highly doubt Respawn will be able to achieve the 66% bandwidth usage reduction needed to support a 60hz tick rate.