I treat interactions with people at work as being very "in the moment", very transactional, just doing the minimum to realize the goals of our work and the company. I don't invest time to build relationships at work beyond that. With my group of friends, I don't see them at work. I don't have many friends but with those that do, I still care about. Far less stressful compared to building genuine relationships at work.
Might be something to do with the workplace setting and money being involved in work. I don't get how transactional behavior in professional settings became taboo when money is at the center of most of it anyways. Nothing personal, just business.
My life shouldn't revolve around work or the people in them, but I do still want it to be stable enough in order to financially support my life outside of work. Can I have it both? In other words, low-investment, high stability work, in tech. Maybe that's a unicorn job in tech, I don't know.
You are tasked with solving business problems and most of your effort is in understanding and modelling the problem correctly. How do you understand the problem in the first place? Do you talk to the business team, end users etc? Is this part of your bare minimum?
You get struck and want to double check with someone. How do you do it? Is this also bare minimum?
Someone else gets struck and want to check with you or they do not understand why you solved something a particular way.. This also needs interaction. Is this also bare minimum?
If you take all of these together, you do interact quite a bit with your coworkers to do the bare minimum to do your job. I do not know what is specially transactional about any of these, but if you try to be pleasant when you interact, that is all that is asked for. No one is asking you to invest time to build relationships beyond work.
However, if you do build such relationships, you might find it useful and pleasant in long run. Maybe you might be looking for a job or your team might be hiring. You need a recommendation on something you are not an expert at or as simple as you are visiting a new place and would just want to socialize.
In the long run, I have found that good relationships (doesn't have to really be "friendships", but at least pleasant working relationships) advances one's career, because then the person has reason to believe you won't knife them in the back the first time it's to your short term advantage to do so. If they ask you for help with a work problem, will you just help them fix whatever it is, or try to make sure everyone else sees you fixing their screwup so you look better (and they look worse)? If they need to discuss a half-formed idea with someone, will you help them thrash out the pros and cons, or will you use the fact that their idea wasn't fully baked, or maybe was even fatally flawed, to show everyone in the workplace that you are smart and they are not as smart? It is a lot easier, and a lot more productive, to work with people who you can trust to at least somewhat care about your well being.
None of this means you have to be attending their wedding or godparent to their kids. But if you have a few beers (or whatever) once in a while, it builds some trust that helps people work together more productively. Like unit tests in code, or payments for insurance, or time spent on safety, in the ordinary course of things the payoff is not obvious, but good working relationships help out a lot, and a basic minimum of socializing helps establish that.
Again, just my anecdotal experience.
I don't see it as taboo, but when I'm spending eight hours a day with the same group of people, it's just less exhausting if you enjoy spending time with them. If I get to know my teammates and have stuff to talk to them about in downtime, it's less boring than just keeping my head down and not interacting with anyone. Most of my work friends aren't people I'd actively seek to spend time with outside work, and usually I don't keep close contact with them afterwards, but even as someone who's pretty introverted, I would burn out way faster without any sort of social interaction at work.
There's also networking which is a way to connect with many people. I wouldn't call it friendship but it keeps you friendly with many people. There are many books on the subject so grab a few and get the gist.
You could also try and not do that. You don't lose anything from building relationships and it might make work more fun.
Yeah, most likely these relationships will die when people leave, but c’est la vie.