At every job I've ever worked, you're paid for your output, not to socialize.
If the manager chooses to deliver business value by hiring humans instead of robots, the manager is obligated to care about the fact they are human and help them improve their productivity, to ensure that effort the company spends training the employee is not wasted if they lose morale and leave, and so forth.
A manager who ignores these responsibilities might be great at pursuing an ideal, but their job is not pursuing an ideal. Their job is delivering business value.
If the human you hire needs to socialize to be productive, that's no different from the printer you bought needing toner to be productive. Telling a printer without toner "You're paid for your output" is shirking your responsibilities.
(There are certainly a lot of managers—and a lot of businesses—that are more interested in pursuing some philosophy of how business should be run than effectively delivering business value. They are objectively wrong.)
> At every job I've ever worked, you're paid for your output, not to socialize.
Of course, but if socializing increases output, then aren't they the same thing?
The idea that you can just hire people who will never feel lonely (or have some other problems in their life) is in itself quite amusing.
There are three kinds of power in an organization role, expert, and relationship. Role power is actually the least effective and relationship power is the most.
It took me awhile to learn that. I've gotten a lot further in my career over the last 10 years than the 10 years before that based on building professional relationships and networks both inside and outside of work than I could have solely by becoming more of an "expert". I know people who are just as smart as I am and many who are better technically who haven't gotten as far because they don't build relationships, don't know how manage up, and can't interview well.
I work at a company that has grown and gotten very beuracratic. Other people on the team - including managers - who aren't as effective at getting things done because they have to go through official channels. I've been able to just send a message with a request directly to a person who I knew could do it, get it done and then go through the official process for documentation.
Management is not required to keep me happy, but I'm also not required to work there.
I don't socialize at work to gain friends, I socialize to gain allies. I've had 5 jobs over 10 years.
The funny thing is, for all your cynicism, the world is actually far bleaker than even you paint it. A manager sees being friends with your cow-orkers as a lever to extract unpaid overtime.