I was real heavy into musky fishing for around 45 years and for the most part kept it old school but that was just my preference. I always did well and would often boat 75 to 100 fish a year with 2001 being my best year with 115 fish in the boat.
I never even had a FF until 1999 and then I put a GPS at the helm to watch for the depths I wanted and to track my drifts and keep track of sunrise/sunsets. I had a small 5" FF at the helm and another at the bow and that was it but they were more for finding weeds than anything else. Never used them for looking for fish. The vast majority of my fishing was casting to reeds or weeds and rock piles and some trolling when I needed a break from tossing big baits. One of my favorite methods was night fishing in total darkness with no electronics at all. Just a headlamp to get my bearings once in awhile then back to the darkness and the light again to release the fish. To me, that was totally pitting myself against the fish with no outside help.
To me that's what fishing is all about, trying to think like a fish and figure where they are and what they want to eat.
I've got nothing against the guy that has a boat load of TV screens that he stares at all day and more power to him but to my mind that's not fishing when you use electronics to do all your thinking, but again, it's just my preference.