You will probably ban a lot of VPN users as collateral damage. VPN providers often use these small and relatively cheap providers for their endpoints.

You may be fine with banning those VPN users, or even want that - lots of bots will try to hide behind "legitimate" VPNs - but one has to be aware of this consequence at least, especially considering that more and more people seem to use them - probably also thanks to the aggressive "sponsoring" certain providers such as ExpressVPN do on e.g. a wide variety youtube videos.