Good question. The answer is, because there is no Normal FOV on Artisan .
Now, you probably would want to disagree (especially, if you are an Artisan owner, or have already seen the headset), because there is a configuration option in PiTool called “Normal”. The problem is that Pimax seems to be making the FOV nomenclature as they seem fit. So while at other headsets (Pimax 5k+, 8k+, 8k-X) “Normal” means ~ 140° horizontally, on Artisan Normal means something between 118° to 132° depending on your IPD.
When (originally) categorizing Pimax headsets I decided that Normal in Pimax brand would mean FOV > 135°, regardless how Pimax will name it in PiTool. (This inconsistency is also present on other Pimaxes, where Pimax markets something as Normal at a higher refresh rate, while it actually is the same as Small at a lower refresh rate).
The other reason why I do not care is that Pimax is famous for silently changing specs, FOV names, and feature behaviors, as they like, and I am too lazy to follow their games.