It’s not only a matter of taste, but probably also of screen size.
On my tablet, I usually collapse most of the sections, so I can still see when the person to whom I have sent a chat message is online in chat. Therefore, the DMs section has to be visible. But I also use the top section a lot, so scrolling to the bottom once does not fix it.
As you can see, even if all sections are collapsed, it doesn’t work to see DMs and the top section with the additional space, whereas I was had space to open some sections before.
That is also the reason why I don’t use the chat sidebar. The chat button needs a lot of space
