The key question here is what is meant by "fully cooked". Cuts of meat with lots of integrated fat do not dry out, even when taken to temperatures much higher than the USDA safe minimum temperature. For example, a pork shoulder or beef brisket might be safe to eat at 145 degrees internal temperature, but will be significantly more tender if cooked to 200-205 degrees internal temperature. Ribs would be similar. At 145 degrees, the internal fat has not begun to render yet, and the meat will be very tough.

I watched the linked video and didn't see a temperature recommendation, perhaps because ribs can be difficult to probe accurately. There are a couple of ways to check that ribs are done without probing for temperature which are documented by Amazing Ribs. The site is geared towards barbecue cooking, but this applies equally to oven cooked ribs.