Fair point about my source and statement. The main issue I have with your earlier statement is that you say “realizing and describing” equals discovering.
A proper theory at least needs some proof, be it purely theoretical. Otherwise one could argue that people discovered flat earth, there’s plenty of descriptions on how it works floating around. Having purely theoretical proof also means I do not agree that theoretical physicists can not discover things. Einsteins discoveries were all substantiated by rigorous mathematical proofs.