Sentence:  That setting enables pre-8.0 clients to connect to 8.0 servers until such time as the clients and connectors in use at your installation are upgraded to know about caching_sha2_password. However, the setting should be viewed as temporary, not as a long term or permanent solution, because it causes new accounts created with the setting in effect to <WSD>forego</WSD> the improved authentication security provided by caching_sha2_password. 
Meaning of the word marked with <WSD> tags:  (nodot=1); to abandon, to relinquish