Again, I not quite sure what to say... Neither in Dev or Win11 do I find nor recall, a Setting to turn on side bar... it is accessed, by default, via Rt Clk menu; has been that for a very long time, now.
No default on that Side Bar.
Also, I found one machine with the Edge Bar that you mentioned, but weird way to get to it.
B.T.W. This one is on Windows 11 GA and has the collapse button. 😎