A few years ago, I was at a client's site and found their two core development teams sitting in a large room. There were two large table with three people along each table, and two end tables with two people on each. A total of ten people in the room, each with two monitors, wires, mice, keyboards, etc. They were placed in that room, I was later told, so that they could collaborate. When I asked if it was working, the manager said, "yes, it's been great." When I later asked some of the developers, the responses varied. The word that kept coming up was, "disruptive."
Collaboration is often the goal of managers when they gather up IT and put them in the room together, and this model has been shown to work, but as with every model, even a stopped clock is right twice a day.
Creation, which ultimately is what IT is, is a study in collaboration, but it's also a a study in the organic process of bringing something into the world. It's a hard thing to put boundaries and definitions around that. If a manager reads an article that says, "putting your devs in a room will increase productivity by 25%", they may blindly toss their team into a room together and hope for the best not realizing that the 25% increase, like most things, is based on certain parameters.
If you put your back end server team in a room together to solve an issue which impacts all of them, your productivity will go up. If you toss your back end server team into a room with two of your UI/UX devs and toss in a DBA, none of whom have any real skin in the game of solving the back end bug, you may find that conversations may occur which distract, disrupt, or prolong the ultimate goal which is reaching the solution.
As IT managers, the goal is to foster a creative environment where those who are strongest on your team are put in a position to foster and mentor those who may be more junior, with the end goal of elevating everyone to a level where they can execute as a team, proficiently and effectively, whether they are sitting in the same room or on different sides of the world.