It's not like it's random people every time though. There tend to be regulars in certain discussions and interest groups. Just like forums and chat rooms (on which I've definitely made connections with "randoms" due to discussing shared interests online and having a persistent identity there.

in a huge company sure but in smaller startups it's fine, it's nice even.

i've been at companies with 10 people and 10s of thousands and in between and obviously this stops holding true at a fairly small number of employees. but there are plenty of companies of the size that this works for fine.