To be honest the noise/volume of the current F1 engines don't particularly bother me all that much & on the whole I really like the current formula. They may well be quieter than engines from the past but there still producing a lot of power (I heard it mentioned recently that Mercedes are close to 950bhp) & I like that there harder to drive than the V8's they replaced because of all the extra power/torque. I also appreciate the technology, Thats always been an element of MotorSport in general that I like to dive into & try to understand as much as possible.
Looking back I did love the sound of the V12's, V10's (Was never that fond of the V8's F1 was running from 2006-2013, They were loud yes but I was just never fond of the actual sound) & things like the Mazda rotary engine but to me the sound isn't why I watch, I watch to see the cars been driven by the drivers, I watch for the speed, performance, Technology & of course the racing.
Formula E cars are quiet but I still watch every Formula E race because the racing is generally pretty good & the cars are still going more than fast enough & I'm really interested in seeing how the technology improves over the next few years.
Whenever this topic comes up I always fully understand those who hate on the current engines & who miss the noise of what we had before, But speaking personally as I say it really isn't that big of an issue for me.