My grandfather had a form of this! Luckily it was treated quickly, but he also ran into issues convincing the doctors that's what it was. Not sure why.

American doctors, working for a large or investor-owned health-care organization?

In hindsight - the hospital that "took care of" my mother made ~100X the revenue running expensive tests on her - in just a week - compared to what an honest, competent doctor would have made over the first year of successfully diagnosing and treating her.

Why is loss of eyesight not listed among the symptoms or consequences?

Because Wikipedia is a so-so source of medical information?

Damaged to eyesight is the first bullet point here...

> https://my.clevelandclinic.org/health/diseases/15674-tempora...

...and the last bullet point here...

https://www.mayoclinic.org/diseases-conditions/giant-cell-ar...

...and the first "if left untreated can cause" thing mentioned here...

https://www.webmd.com/heart-disease/arteritis-giant-cell

...and you probably noticed that all 3 of those prefer to call it "giant cell arteritis".

Because no one took the time to find a high quality secondary source and add this fact to the article yet.