I shoot Nikon. I have a D7100, upgraded from a D70 in 2015, which was an upgrade from a N60 in 2004.
I also shoot a Nikon FM10, which is the Nikon version of the mechanical, non-automated, cheap camera that everyone is lamenting over. (Still available new! Also, made by a third party, Cosina, so NB4 “It’s not a real Nikon!” )
I figured going through the use case for each camera to take a picture may show the differences between the cameras more fully. I think there is a lot of confusion about DSLRs versus Manual SLRs…
Shooting the D7100 requires some setup before the shoot, using buttons and the command dials. I almost always shoot in M (Manual) mode, so set my ISO and White Balance.
I set the same functions on my FM10 through a process called “Loading my Film”. (Also, don’t forget to lift up the shutter speed dial and rotate to match the film speed, otherwise your exposure meter will be off.)
Then, shooting the D7100, I twist a dial (not marked) to set my shutter speed (which is displayed on the top deck of the camera and in the viewfinder) and a second dial to handle the aperture (also displayed in the viewfinder and top deck). If the lens I am using has an aperture ring, I can twist it instead. There is autofocus, and a switch to turn it off.
For the FM10, the shutter speed is set by the dial, and you have to use a lens with an aperture ring. The info is not shown in the viewfinder; you have to look at the lens and dial to see what it is. (Other models did have this information shown in the view finder.)
I find that I have to pull the D7100 away from my face much less while taking pictures than the FM10. I have a lot more information available in the viewfinder.
I also find that I use the menus in the D7100 very rarely. Almost everything I want to do on a regular basis has a button. My #1 Menu diving item is swapping between my manual lenses, so it “knows” which lens I have on the camera. Other than that, it may be months between times when I open the menus.
My understanding is that almost all camera brands have similar setups for at least some of their DSLRs.