I did a firmware update in 2015, mainly because I wanted to see if I could do it with a virtualized Windoze running in Mac OS X. It worked. I decided to quit while I was ahead, and haven't done so since.
Unless something is malfunctioning, or you want to add a component, there really isn't an imperative to do it. Even if the probability of bricking it is small, it would fsck to have to pay someone to unfsk the system.
I'm assembling a bike for someone else at the moment, and will have to do firmware updates on her system, since I am mixing generations of components. I can hardly wait.