I thought the exact same thing and recently put it to the test, and my estimate now is that in my case in about 15 years the time spent on creating the automation will likely have been payed off: 2 machines every 5 years, let's say 2 days to get them manually installed/configured completely vs about 6 days spent on the automation now. At least, if my stack or aplication preferences etc doesn't change too much. As a bonus: I learned some new stuff while doing it. So in the end for me it was worth it because of that learning and because I really dislike repeatedly installing stuff, waiting for installers to complete, customizing, ... But let's see again after a couple of iterations if I still think that way (e.g. if it turns out the automation scripts require too much caretaking, as per xkcd).