I suppose the only way to reduce deterioration is probably not to play with them as much, which kinda sucks. Me personally I try not to turn my minifigures' hands too much when posing so they don't become loose in the future; experienced that with my brother's Rohan soldier.
And yeah, I've noticed cracks forming in the hands of the newer minifigures too, especially in the licensed theme. Nothing too major like the accessories falling out but they're visibly there.