This topic seems to come up time and time again on here. As someone young and new to the industry I have only ever experienced open plan offices, so I don't really know what the alternative is like. However I'm inclined to say I don't think I would enjoy cubicles or private offices. I feel like you'd miss out on so much collaborative effort and serendipitous & spontaneous conversations with colleagues that solve problems out of the blue. I also think it's just plain isolating being on your own in a room all day. What's wrong with just putting some headphones on if you want to put your head down and do some deep, quiet work?
Having said all that as I admit I haven't experienced the alternative so I'm open to being convinced I'm wrong.
I have 300 people on my floor, the group closest to us is from business and spends 2/4 hours a day on the phone. It saddens me because the largest openly claimed benefit of Open Plan offices is "increase collaboration". What I literally see is people locking themselves with headphones and trying to hide in rooms to get some silence. I mean, people literally have to walk around teams to go to the toilet or get a coffee.
I'd like team size cubicles. That would sound to me like a good compromise between collaboration, and deep work. I'm sure people would open up more. In fact, it is how it was setup at Bell Labs back in the time [1], not the pale copy we see everywhere today.
A bit like Agile has become Scrum I'm guessing :).
[1] https://aquicore.com/blog/bell-labs-office-design/