Hi sorry I was looking for the same thing you are I prefer the layiso command to freeze all the other layers not lock them I just like it for visual purposes. So I got on to this chat to try to figure it out but it did not help much so I went to the help menu in autocad and figured it out myself. So I thought I would help you out too.
ok so if you type layiso then type s for settings you are given two options:
off -which this settings freezes all other layers besides the one you select.
lock and fade - which this setting locks and fades all other layers.
So you want to set your setting to "off"
Hope this helps
There used to be a way to isolate layer(s) by freezing/thawing instead of on/off, and I actually liked that way better, but it's been several years since I've seen it, and do not even recall if it was in the program or a lisp routine.
Once I found the option to turn layers off completely instead of simply dimming them (I hated that, did not serve the purpose, IMO), I was able to adapt, but would still prefer freeze/thaw.
Personally, I'd like to see it as an option without having to go the "Why don't you do X" route.