I think T-shaped people are usually specialists-turned-generalists, for example good software developers who later on became managers. As a manager you have to

I think T-shaped people are usually specialists-turned-generalists, for example good software developers who later on became managers. As a manager you have to be a generalist, and you usually have hundreds of small tasks, so no deep dive in one topic, but surface level in many. In my experience these people are definitely better managers (unless they suffer of old physics prof disease), but I don't see the large benefits for more specialised roles. The more I switch to being a generalist, the less I can actually deep-focus, and talking to friends and colleagues, it doesn't seem like I'm the only one. That said, interest and curiosity about other fields, especially the ones you actively work with or neighbour is probably always a great quality to have.