Using a script to download free models that you are already permitted to access is generally seen as a low-risk, technical breach of terms of service.
While locating an active, public "CGTrader Ripper" repository on GitHub can be challenging due to platform enforcement, these tools often have identifiable characteristics. A 2024 version of a tool sold under the CGTrader Ripper name, for example, advertised features including: cgtrader ripper github