It depends on the tone of the text. You don't put emojis in a scientific, wikipedia-type article, but you can use them in informal environments. I wouldn't like to see emojis in a product description of a smart TV either, because (in my book) emojis scream unprofessionalism and that's not what i want, when i'm planning to buy a TV. But they can work in other environments such as beauty products for teens, anything which is geared towards a mainly young audience.
Where emojis can work extremely good is the subject line of emails. Not because of their original concept, but because they make the emails stand out in the recepient's inbox. They're still relatively rarely used, maybe once out of 100.