The article asserts, but provides no real evidence that steampunk has "died".

I wanted to refute the author's claim by looking at google n-grams, but the viewer cuts off in 2008 with the steampunk n-gram still going strong...

Instead I present anecdotal evidence that steampunk is not dead:

1. The presence of an steampunk section in my local Spirit of Halloween store.

2. The release of Carnival Row this year by Amazon, which I believe fits the bill close enough.

3. A continuing new release of steampunk novels (https://www.goodreads.com/genres/steampunk)

Flimsy evidence, but perhaps enough to refute the death of steampunk, which is a strong claim.