The disadvantage of embedding assets in the Bitcoin blockchain is that the Bitcoin rules must be followed as originally written, and the Bitcoin nodes are unaware that assets are being embedded.
Other token standards like ERC20, ERC721 and ERC223 are built on Ethereum or other blockchains that support smart contracts. A different problem exists when using these smart contracts. Since the Ethereum network does not natively recognize these smart contract tokens, it is currently unable to protect against some common problems. Smart contracts can be confusing for users as there can be multiple ERC20 tokens with identical names. The only distinction between contracts with identical names is the contract hash.