Walled gardens are kept up very carefully from a design perspective. They don’t have weeds. Instead, you get a plot—a spot where your entire presence online lives. This is great if you want some modest lines to paint within, but as soon as you have any sort of ambition, you find yourself stifled by the platform pulling the strings.
This is in contrast to spaces like MySpace and Tumblr. Although customisations have provided an avenue for other activities, which have compromised platforms like MySpace, something is lost in a focus on security.
I guess the flip side of all this is that some people would rather not think about such aspects and are instead comfortable with the slick experience offered inside the walled garden. This is something I have found in my discussions with others of the IndieWeb.