Gluck's finale is regarded as not sufficiently distinguished, but this is wrong.

The real finale was sung at Mezieres and it was found that it was not at all common, but that its frank gaiety was in the best of taste.
Gluck had no scruples about grinding several grists from the same sack and drawing from his old works to help out his new ones.

So the parasitical aria attributed to Bertoni was written by Gluck in the first place in 1764 for a soprano.

He wove this into his opera _Aristo_ in 1769.

This is also true of the trio, _Tendre Amour_, which precedes the finale in the last act.