Will periodical increasing and decreasing cryptocurrency supply peg cryptocurrency to dollar effectivelly? As far as I understand, in order to make cryptocurrency pegged to USD we need somebody to take the risks of exchange rates. So, if ratio CRYPTO to USD is at a given time 1CRYPTO:1,1 USD, then we increase cryptocurrency supply by 10% and it will return to 1:1 parity? And conversely, if at a given moment ratio is 1.1 CRYPTO: 1 USD, we decrease money supply by 10% and ratio will return to 1:1, is that right?? Increasing and decreasing amounts of cryptocurrency in existence in response to price fluctuations can effectively peg 1 crypto: 1 USD or not??
No, it's by no means a guarantee of a peg.

The cryptocurrency's actual exchange rate will be determined by people's collective expectations of the present and future value of the cryptocurrency relative to the dollar.

Most importantly, the exchange rate will be driven by how much people trust that they will actually be able to get a real dollar in exchange for a unit of the cryptocurrency.