SKAGs are dead. They simply aren't viable in today's paid search environment. However, this eulogy isn't without a bright side. In a way, close variants basically represent Google's incorporation of the SKAG model into the definition of exact match.

Should I use SKAGs?

SKAGs sound like dirty keywords, but they're actually one of the best ways to get more ad clicks. More ad clicks is great because that increases your click-through rate (CTR), quality score, and the money you make.

Are SKAGs dead?

Yes, Single Keyword Ad Groups (SKAGs) are Dead and now we're competing again ourselves for close variants in other groups. Then in July 2019, Google announced they would extend close variants to board and phrase match. So, the benefit of SKAGs is still there, it just matches for close variants.