Well, as you asked..
It's very busy, frilly, flouncy, frou frou frock for maybe a 17-20 year old at a push, imo. Sure, anyone can wear it, it's not forbidden, but I most definitely wouldn't. I'm 36. It's not the question of figure/slimness, I look similar to the model in the photos, skinny and slightly taller than her. But I'd feel stupid in it, as if I'm trying to re-live my teens.
At 50, no chance. The mutton thing is not very nice to say, but I'd feel exactly that. There surely are better dresses than this. Nothing against mini or showing skin- go for it- just not all those frills and juvenile 'playfulness'.