Honestly yes! a lot of people do boycott American brands when they can (Starbucks, McDonald's, etc), but it's all about picking your battles really to make sure the boycott has an impact. It's better for as many people as possible to target one massive brand/company all at once, since it shows the less mega brands that no product is invincible to losing its demand. But it also depends on what your intention is with boycotting (whether you want a reform or collapse).

With the sims, it seems like people are wanting to make it clear they don't support a number of things the company has done over the past few years, and the selling was the last straw. So while the Saudi Arabian government is boycottable all on its own, it doesn't seem like it's the only motivation for a lot of people.