I think Bitcoin will protect against inflation, and even hyper-inflation, if the demand for it continues to keep place with the growth in supply. That will only happen if people continue to use it as currency.
Yes, bitcoin can protect us from inflation and there is no possibility of inflation because of its limited supply which cannot be increased. It may be decreased as those wallets whom private key are lost, they bitcoins stored in them are unrecoverable.
The main thing to consider is that people should use it as a currency and if it is mostly used as a trading assets, then we can never get rid of fiat.
I think it will be difficult to get rid of fiat because irrespective of bitcoins usage as a currency, there will always be many who would prefer to have it as a trading asset and am sure we do not expect it to correct inflation this way. So, it is kind of clear that bitcoin cannot help control inflation, it is the government putting certain policies in place, and one of such could be complete adoption of bitcoin as their only means of exchange