The issue is not so much the presence or absence of thought activity during meditation. Rather, the issue is the degree to which ones thought activity is driven, unconscious and fixated.
The great majority of human beings are literally addicted to thinking. Even the most wretched substance abuser can go a few hours between “fixes,” but most human beings cannot abide even for a few seconds without some sort of “thought fix.” If there’s nothing significant to think about, we fill the void with fantasy and trivia. Simply stated, meditation breaks the addiction to thinking. One is then in a highly desirable situation. When you want to have a complete experience of hearing and feeling (for example as you listen to music), you can do so without being compulsively pulled into thoughts which are not relevant to the music. When you want to have a complete experience of tasting and feeling, as when enjoying a bite of food, you can likewise do so. On the other hand, when it is appropriate to think, you find that your thinking abilities are vastly improved.
Shinzen Young