No, every engineer should not blog. It is hard enough to find the right information when you have to shift through clickbait and the signal-to-noise ratio is abysmal. If I was interested in assessing someone's caliber, I'd rather look at their Github than their blog. Anyone can write a blog post, not everyone can write good code. Blog if you have some insight into technology that hasn't been already elucidated or if…
But can "anyone" wrote a good clear blog post that explains a problem, talks about a solution and some of the plusses and minuses of alternatives? Can "anyone" maintain a blog for a number of months or years?
I'd say these are differentiating features.