? There is can be 10 times more miners and hash power, than now, and bitcoin output will be the same.
That's not always correct. It is correct at the start of a new 2016 block difficulty, but not after that.
If network hash power is 10THash/sec, and a new difficulty is calculated, the difficulty will be set to work out to be around 6 blocks per hour. If you then open up 5Thash more for the next 11 or so days, it'll be creating 9 blocks per hour, thus bitcoin output is not the same with more power. If the extra 5TH is sustained until next block cycle,
then the new difficulty will slow down the block creation to 6 per hour again. It's about as constant as the change in hash power over time.