I don’t know in detail about the later interpretations of the Buddha. But true meditation is the most scientific approach possible. It is not numbing the mind, it is staying aware, staying as awareness with your experience. When awareness merges with an object, our understanding evolves. We gain insights. By staying aware of the ‘outer’ and ‘inner’ world (which are actually one but we believe them to be separate), we can see things as they are.
Thinking is a very small part of the mind, but most humans are conditioned to mostly focus on their thoughts and live from there. This is a very limited experience and their understanding of life also remains limited this way.
Pure zen is living life in its entirety with awareness, not just getting locked into thoughts living with little awareness of anything else. If one can live life in the moment with awareness, by and by a quality of stillness develops in the mind. The origin of the Japanese word Zen is Indian, it is Dhyana. The word Dhyana according to my understanding is pointing to an evolved state of consciousness where this quality of stillness has developed. There is the experience of pure awareness, great peace, connectedness/even feeling one with the Divine Love energy within. This is not a dull mind, rather this is consciousness living life with great intensity. Prioritizing the cultivation of this state develops the most scientific mind. The mind where awareness merges with whatever object is being experienced. The mind where awareness eventually awakens to its oneness with all forms. The true scientist is one whose understanding actually evolves. The true scientist gains the mastery of forms because of this evolving understanding. They don’t just remain in the small thinking part of their brain, missing the opportunity to actually merge as awareness with the phenomena they are studying.
With an ignorant approach, creating a dull mind is also possible. I heard that for example if mantras are mindlessly repeated, the mind can become dull. This might be happening in some monasteries where they lost the way of the original Zen. It is possible to forget that the essence of this all is living with awareness, living as awareness. When it is forgotten, by and by the practices developed with intentions that can support the cultivation of this awareness can lose their purpose because whoever practices them has lost connection with the original intention.
One should not try to stop thinking. This is not healthy. Rather, one should work to awaken to the state where thoughts are transcended. Thoughts decrease on their own when they are no longer needed because a higher intelligence is starting to take over. This is our own higher intelligence. This article explains what this transcendent higher intelligence is. (written by a person who has continual direct experience of it).