Sentence:  But I also think, “They're looking for a <WSD>unicorn</WSD> — a magical designer who can solve all their problems.” It's too bad <WSD>unicorns</WSD> don't exist. … I have never met a designer who is an expert in all those skill areas. … Even if you find a <WSD>unicorn</WSD> designer with all those skills, actually doing all those things at your company is a huge amount of work. 
Meaning of the word marked with <WSD> tags:  A person with multidisciplinary expertise (due to rarity and value), especially three or more skills in a young field such as UX design or data science (e.g., domain knowledge, statistics, and software engineering).