Any stable linked to fiat automatically increases inflation by the amount of its issue.
Do you mean anyone can simply create a stable coin without a backing equivalent asset?
Nope, regulations regulate how to issue stable coins especially fiat or other tangible commodities reserves where it cannot be withdrawn as long as its stable coins are in circulation (unless they are renewed when obsolete), and issuers must report their reserves every period. Then coin-stable inflation occurs as fiat represents it.
The total capitalization of stablecoins has exceeded $180 billion and further growth is endless.