I won't be boycotting Nikon, mainly because I don't buy Nikon anyway.
If their scopes are anything like their lenses then you'll need a pocket book of caveats depending on the age of your gun..
The nikon f mount will work on any nikon slr.. except if you need aperture index, except if you need an AF motor, on an fx body but at 3mp etc etc etc.
It's a pretty nasty advert, but then it probably appeals to the mindset of the nasty people who shoot animals for fun (and I am clear to make the distinction between fun and necessary culls)
If canon made a similar advert or made a similar product would I boycott? Probably not. Theres all sorts of reasons to boycott all sorts of products.. some folk might boycott a japenese product because of their historical reluctance to accept and apologise for war crimes, some folk might boycott an israeli manufactured bag because they don't like the way the palestinians are treated.
I grew up in a lefty house, so nestle was barred at one point over the african baby milk powder, outspan over apartheid etc. but these companies are still in business. I'm sure nikon will survive. Despite recent attrocities recreational gun users don't seem to putting down their arms any time soon.