That's a valid point.
But this article has explained to me why the ESC grant-seekers are seeking government grants. The article exposes their underlying motivation and is a useful addition to the argument contra, although not essential, as you point out.
OTOH, the article also notes that there are non-government-funded ESC efforts also underway, both here and abroad, which tells me that there's more to this than a bit of fraud. Kellmeyer's opinion about motivations is probably wrong The researchers involved are probably not "frauds," in the sense that they're sucking at the government teat for something they know to be unworkable. More likely, their motivation is to have steady money available for something they think they can make work.
In fact, the more I re-read Kellmeyer's article, the less I like it. He appears to be untruthful in some very important areas -- falsely accusing researchers (most of whom are earnest, even if morally on the wrong side); and undoubtedly misrepresenting the scientific case as well. Such slimy antics have the unfortunate side effect of making the underlying (and correct) point seem slimy as well.