I don't think anyone thinks the value resorts "suck": just that other resorts are a better fit for their particular family. For me, it comes down to a value proposition: for an extra $25-$100 per night, I can stay at a moderate (or even in a deluxe DVC studio on rented points), which offers appreciably larger rooms and bathrooms (typically with an extra sink, a more private changing area, etc.) and often an additional Murphy bed, all of which are valuable and much-appreciated amenities for my family now that my children are nearly teenagers. (Not that long ago, the values also had only full-size beds, which means taller/larger adults like my 6'+ husband were dissuaded from staying there, and no in-room coffee makers, so we'd have to bring our own - a big hassle since we travel carryon-only.) The values are also themed more toward those with small children.
My sister and her family stayed at AoA twice when their kids were toddlers, and they absolutely loved it. However, as their family got bigger, the value-sized rooms were no longer convenient for them, and the kids no longer appreciated the cartoonish theming, so they moved on to other resorts.