The passage suggests that attending TV programs by a university professor will increase the reputation of the professor and the university, and helps the public learn scientific knowledge. The lecturer, however, refutes these ideas.
First, the lecturer states that when a professor attends TV programs, he will no longer be considered as a serious scholar among their colleagues, therefore he will not be invited to future conferences and academic meetings.
Second, as the professor points out, when a professor attends a TV program, he wastes a lot of time preparing the contents for the program, traveling, etc. He could have used this precious time doing research at the university, help his students in his office, and do university-related business. These contradict the ideas presented in the passage that a university professor by attending TV programs will increase the donations and the number of applicants to the university.
Third, the passage suggests that the public get the opportunity to learn many scientific facts from a professor who attends some TV program. However, the lecturer states that the purpose of TV producing companies is not to introduce real scientific materials to the public audience; they merely want some entertaining programs and only exploit the reputation of a professor to act in a way that a not knowledgeable reporter can do, too.
In sum, attending a TV program brings scientific value neither for the professor, nor for the university he teaches at. This only squanders the time of the professor, and prevents him from doing what he is required to do, i.e., academic research.
TOEFL listening lectures: What is the main difference between a fad and a trend?