Food Safety News is a periodical published primarily for the food industry; and has a "bias" (if you will) toward making sure that the readers (people in the industry) are aware of potentially hazardous practices that could impact the incidence of food-borne illness.
The article specifically calls out iced tea. In a great many facilities, iced tea is served from a large (gallon+ size container), especially self-serve at a buffet style restaurant. The 8 hour limit is likely referenced because you're supposed to make sure things (work prep surfaces, etc) are cleaned and sanitized AT LEAST ONCE every 8 hours. One of the health inspectors at a facility I rented from routinely checked the cleaning schedule of the ice machines because people are notorious for forgetting to clean them and that's what she was going to ding the facility for. She didn't count on the caterers being exemplary practitioners of food safety 
and she even commented on it!
Anyway, as mentioned, as long as you're brewing the tea properly (with boiling water) and using a clean vessel to boil the water in and a clean storage vessel (to store the brewed tea in) you should be fine.