I wouldn't hire someone just because they're entertaining. But I might not hire someone otherwise qualified if they're not. And I'm not even in the habit of socializing with co-workers outside the job. But the job is enough hours with someone that I'd much prefer to enjoy their company.
I'm not sure why you keep assuming the best programmers are boring or unpleasant. I've found the opposite to be true, generally.
I assume nothing. I'm just pointing out that being "boring" or "entertaining" is completely irrelevant to whether someone is suited for a programming job, and that unless you're running a lifestyle business where enjoying your work day is more important than delivering results for your customers or getting paid, you're doing your company a disservice by hiring people based on these kinds of irrelevant characteristics.
I'm not sure why you keep assuming the best programmers are boring or unpleasant. I've found the opposite to be true, generally.