> well established from multiple studies, easy to google

That's not all of them. You can find systematic reviews and meta-analyses walking trough them all. Easy to google. 50-100 mg per day is OK and possible has some benefits, if you go to more than 2 grams like you suggested for health person, there is no evidence of benefits, only harms.

There are a large number of studies on this topic, in part because vitamin C supplements are so widely used and easily accessible. Several people have already shared relevant research in this thread.

Before promoting high-dose supplementation as universally safe or beneficial, I strongly recommend doing more in-depth research. It’s important to understand the potential risks especially since this kind of advice, if followed without medical oversight, can have serious health consequences.