While it’s true that the standard can be followed to deploy bridged USDC on any EVM blockchain, USDC already exists natively in the Cosmos and Polkadot ecosystems:
USDC for the Cosmos ecosystem is natively issued on Noble and can be transferred to Cosmos appchains via Inter-Blockchain Communication (IBC).
USDC for the Polkadot ecosystem is natively issued on Asset Hub and can be transferred to Polkadot parachains via Cross-Consensus Messaging (XCM).
As such, Circle intends for USDC to be accessed via the established protocols in each ecosystem. However, each sovereign appchain and parachain is free to choose if they prefer to deploy a bridged USDC token contract.