How would topical application work, and what kind of homeostasis effect, from ingestion.
If you are low on vitamin c in your diet, sure. If not, you may not get much benefit from having more.
IMO, everybody should take at least 2g daily in a couple of doses, particularly smokers.
I strongly caution against this kind of blanket recommendation. For most people, taking such a high dose without medical guidance is unwise. Unless a healthcare professional has specifically advised it, this level of supplementation goes well beyond established guidelines.
There is substantial research highlighting potential risks, including kidney damage, associated with high-dose vitamin C intake (as referenced elsewhere in this thread).
Anyone considering this should thoroughly research the risks and consult a qualified medical professional before proceeding.