this was the best strategy for me back in the day. It’s rare there’s more than a single digit number of empty seats on any flights I’ve seen these days - and even those are probably often due to a misconnect or a few. I stopped trying the aisle-window thing many years ago, especially now that we usually travel with kids - doing an A/C/D/F and hoping is just not worth it.

What I do try and do now is book us something like A/B/C/D in a row where F seat is occupied. Again, back of E+ or premium seats will probably be your best bet on most routes, but even I wouldn’t count on it tbese days. Thing being that a single middle between two occupied seats is probably much less
likely to be selected than an empty aisle/window, even in the back.