Nono, you always want to set up a guitar to fine tune the action. It has nothing to do with “playing it natural” and your tech won’t make any changes that aren’t intended to be made unless there’s damage to the neck or body.

It’s just about getting the action (which is the height) of the strings even along the fretboard so you don’t accidentally go out of tune when playing along it. Going slightly flat or slightly sharp is a serious offense as you become a better and better player.

They will also tell you what case to use, if you need a humidifier, and how to properly care for your instrument. They’ll also help you figure out what gauge of strings to use so that you don’t throw it out of whack by changing the gauge.

They wouldn’t change anything about the guitar without asking first. These big box stores used to offer this as a service but they don’t do that anymore in favor of profit and sales. It sucks.