We have been to the Biergarten a handful of times for dinner and we just made ADR's there for our friends and us the night before our wedding.
My DF is a pretty chatty guy in social situations, but he prefers more intimate dining arrangements. I tend to be more anti-social and shy in those situations, though I am polite! Typically I would hate and refuse to dine in a group situation with strangers, but I love the Biergarten so much, it's worth it to me!
I have to say that we actually much prefer to be seated with families with kids because it will almost garuntee us that we won't have to dine with rowdy drunk adults LOL! We did have a less than stellar experience there once seated at a table with a really obnoxious drunk older couple and we could not wait to get out of there. The couple was already drunk when they arrived & I think they thought because we were a couple as well, we would hang out and get drunk with them. My DF & I love the beer there, but we are just not the type to get drunk and rowdy with a bunch of strangers.
We had another dinner there where we shared the table with a family with kids and we much preferred that. The family was focused on themselves, so aside from some polite greetings and friendly small talk here and there, my DF and I were able to concentrate on each other and our meal

We also had fun watching the little ones in that party get up and dance when the band was playing
Our first time there we were seated with a bunch of business men and a newly married older couple. We didn't really know how to respond to the communal tables thing and I think neither did the couple, so we tried to force fake conversation, but we had zero in common & just did not "click." It was uncomfortable feeling like we were forced to get to know each other. After that we realized though that, just because you are sharing a table with strangers, doesn't mean you have to be forced to socialize with them, aside from a friendly greeting and maybe a comment here or there if an opportunity arises. My DF & I are usually able to just be polite but form a little bubble and enjoy our meal with each other.
Aside from the drunk couple, we have never had a bad experience at the Biergarten. People are polite and courteous & just there to enjoy their experience as well.
The food is excellent-lots of choices! We always find the servers to be friendly and outgoing. & the band is so much fun!