I know the main difference between altcoins and tokens lies in their structure; While altcoin is a separate currency within its own blockchain, the token operates on top of a blockchain, which facilitates the creation of DApps. So altcoin and token is better? Are any tokens want to develop need to become altcoin?
Nothing is better between the two since there are times when altcins are better than tokens and vice versa. Basically, every token is also and altcoin IMO since I definitely altcoin in my mind as any crypto currency that is not Bitcoin(alternate Bitcoin) which in sense is what token and any other coins existing in the market is. For this reason there is no need for a token to become and develop to be an altcoin since it is already one.