Hello @FireWire33Red 

Thank you for posting on the TP-Link community, and we certainly appreciate all your feedback and feature request(s) here.

As I tried to explain to other users, based on the operating principle of the Guest Network, guest isolation loses efficacy when the router is in access point mode. If guest isolation is forced to be enabled, then clients which are connected to the guest network will not be able to get IP addresses and access the internet. When working in AP mode, the main reason to have the main network and the guest network is to distinguish the two, as some users prefer not to share the wireless credentials with guests.

But this is still something that I can bring up with the product team, I am happy to forward this topic along to the team for visibility again. Thanks!