So I did 7 10+1 draws on various alt accounts.

I averaged about 3 golds per 10+1, which means that chances are, the gold rate really has been changed.

I got a single 6* from the 7 draws, which is about 1-2% chance, which is still within reason of the 0.5% claimed, since the variance on such a small number of draws should be quite high.