It's literally just SO format, but for internal stuff. It's great for when you have siloed teams that have to communicate, especially when you've never met those people. It makes a lot of sense at these large companies, since Uber is just a bunch of small, isolated teams mashed together in large open floor plans. Nobody actually knows each other unless you've worked directly with them or they're notable management.
So for that, it was great (when I was there). I can't imagine this being useful for smaller teams.
Confluence is more long-form, wiki-like documentation, often written by someone with authoritative knowledge. While this isn't forbidden (quite the contrary) on SO or SO for Teams, it's not exactly what it's most useful for in my opinion.
Some of the most awesome engineers contributed a lot, which made it pretty high quality.
You could also ping a person when asking a question, that's usually more polite than pinging over chat with your question.
Some high-touch teams (e.g. software networking, with whom almost everybody has something to say/ask) set up their "how to ask us a question" to post on internal slack. Works great.
Edit: also keeps people more honest when asking questions - SO taught us to ask questions correctly. :)
Current Uber employee
The product is different from wikis or intranets because it's not just about anticipating what someone might need and documenting that. Stack Overflow for Teams gives users the ability to ask a question and people can ask teammates to add knowledge to the platform right in chat. So knowledge itself can be either proactively added, meaning people are anticipating needs, or it can be reactively added, based on an immediate need, like a question.
For your search question - it has basic and advanced search capabilities. You can read more about that here.
https://stackoverflow.help/en/articles/4400196-search-existi...
If you want to read about how it compares to using version control, Confluence, or wikis, there is a case study on switching from those tools here.
https://info.stackoverflowsolutions.com/Enterprise_Elastic-C...
Plenty of times where a smaller company has a ton of internal knowledge that really needs to be on a public SO as they are common questions. It would be incredible to say, we'll let internal users ask questions here and then populate a public set of tags based on that for new/emerging products.
Having it in this format should make it easy to port Q&A over to the public site if a Team decides to make a certain project visible or open source.
I have to work hard against this impulse to continue reading the actual answer.
the search function is bad and I end up using it a lot less. (and often can find better answers on slack)
I think to make SO useful, you need a push from the leadership layer to have all the questions be posted on SO and answered on SO. If you don't push for more questions to be answered on SO, then slack is often better source of Q&A.
And you probably need to maintain and trim the answers (since internal APIs / issues change a lot more rapidly and some answers can become stale quickly)
Basically, not a slam dunk straight away but I can imagine that it is a good idea