How can I disable the “trusted_domain” I want to access from any IP without restrictions for my family and friends
“trusted domains” is not an access control for clients. It is a a control for allowed Nextcloud names or IP addresses of your Nextcloud.
If you host your Nextcloud at home you need a dynamic ip address, dyndns name, Lets Encrypt and port forwarding. Post your settings and your problem.
I wouldn’t like to turn that off as it is a security feature. It has nothing to do with accessibilty as you understand it. Of course you wanna access your server from everywhere, and so you CAN do that regardless of your trusted domain-settings