Well I think instantiating plugins using a controller indeed is a huge time-suck, but controlling plugins is a different matter. Typically when I mix for post I have templates that all have most of what I need already instantiated; EQs, compressors, reverbs, denoisers etc. It’s all in there, so no need to add anything.
I suppose the next thing is what the fastest way to access plugin control is. In the case of the Digidesign setup you’d just select/focus the track and then the EQ section would adjust the EQ on that track. I think we can get something essentially the same going with other controllers. So having a plugin open at all times but have it follow selected track and the controller then defaults to that plugin for encoders. And then switching inserts easily with a button press. Alternatively one could simply open or select the plugin to focus it.
So yeah, I’m with you on instantiating plugins - I’ve never done that and never will…