I have no doubt there was fun to have before Iron missions, but how we play the game is unique to each of us, we all have different preferences (to grind or not to grind) to chase MU or not, for some that is a bit too much like work than just fun.
What works for you, may or may not be the preference of others, I was simply commenting for myself that I am finding it hard to re-focus.
There is no right or wrong way to play, and I have no doubt I will re-focus and change game play in time, just need to re-think it.
As a busy shop owner (and crafter) I chase MU a lot as I try to get as many of my own resources as possible (as both hunter and miner). I do however also like to spend time developing my avatar skills, to make personal progress, and I simply find this multitude of small rewards loses for me the sense of achievement I gained from completion of a long Iron mission.
I have over the years had a lot of fun doing the Iron, bronze, silver missions, and yes sometimes it doubtless cost me more ped than it should have, but tbh I don't object to paying a little for my entertainment.
It is now for me and me alone to work out how I handle this change and where I go from here, it will just take time