I think that in just about every area of scholarly work, ideas are formally introduced and names are made through the medium of formal books and papers. (The ideas are often informally introduced prior to that in discussion.) But sure, presenting ideas (scientific or otherwise) in talks or lectures doesn't discredit those ideas, provided that the ideas had merit to begin with. Of course not, that idea's just stupid. Most of the prominent names in intellectual history have given lectures and talks. The iconic ancient Greeks did and it's how most university instruction is conducted today. It's how scholarship has historically been passed down. Our ability today to record those talks and lectures on video doesn't render what's said bullshit and turn the speaker into a deceiver.