It's a tradeoff. After using ChatGPT for a while you develop somewhat of an instinct for when it might be hallucinating, especially when you start probing it for the "why" part and you get a feel for whether its explanations make sense. Having at least some domain knowledge helps too - you're more at risk of being fooled by hallucinations if you are trying to get it to do something you know nothing about.

While not foolproof, when you combine this with some basic fact-checking (e.g. quickly skim read a command's man page to make sure the explanation for each flag sounds right, or read the relevant paragraph from the manual) plus the fact that you see in practice whether the proposed solution fixes the problem, you can reach a reasonably high level of accuracy most of the time.

Even with the risk of hallucinations it's still a great time saver because you short-circuit the process of needing to work out which command is useful and reading the whole of the man page / manual until you understand which component parts do the job you want. It's not perfect but neither is Googling - that can lead to incorrect answers too.

To give an example of my own, the other day I was building a custom Incus virtual machine image from scratch from an ISO. I wanted to be able to provision it with cloud-init (which comes configured by default in cloud-enabled stock Incus images). For some reason, even with cloud-init installed in the guest, the host's provisioning was being ignored. This is a rather obscure problem for which Googling was of little use because hardly anyone makes cloud-init enabled images from ISOs in Incus (or if they do, they don't write about it on the internet).

At this point I could have done one of two things: (a) spend hours or days learning all about how cloud-init works and how Incus interacts with it until I eventually reached the point where I understood what the problem was; or (b) ask ChatGPT. I opted for the latter and quickly figured out the solution and why it worked, thus saving myself a bunch of pointless work.