I have always cruised in an inside and will continue to cruise in an inside.
I'm a VERY light sleeper and I love the pitch darkness in the cabin.
Love the less expensive cost of an inside. Plus I can take more cruises booking insides vs balconys.
I'm never in the cabin anyway. Even if I had a balcony I would only use it to dry off wet swimsuits.
(which I can do poolside anyway)
The inside cabin and myself are a perfect match.
The inside cabin is not for everyone just as the balcony is not for everyone. Cruisers should book accordingly. If you will get use of the balcony or need light go for it. If you are not going to sit on the balcony save the money and go with inside (or window).
Either way balcony or inside.....It's a cruise...