I have filleted thousands of all kinds of fish with and without electric. I prefer electric for walleye and panfish and feel I get the vast majority of usable meat, with little waste. Sometimes I zipper y bones sometimes not and love the cheek meat, pop those out with electric too. For salmon, trout etc. and halibut I like a quality sharp ( size appropriate) standard fillet knife! To each his own “best” “preferred way! Whatever works for you, practice makes perfect! ?
time spent fishing isn't deducted from ones life