My research journey into owning a puppy.

I am currently deep in the research phase before buying a puppy, and part of that has been looking into different trainers and training philosophies. There is one well-known Hispanic trainer whose name I will avoid mentioning, as I believe he is not allowed to be named on this subreddit. From what I have seen so far, his training system appears effective on the surface. The structure, confidence building, and results in videos are compelling. However, I have also noticed that many people are highly critical of his methods, and that has made me pause. I am trying to understand whether I am missing something important or overlooking potential issues due to limited knowledge or selective exposure. I am not here to defend or attack anyone. I am genuinely trying to learn. For those who are more experienced or knowledgeable:

Any insight, nuance, or recommended reading would be appreciated. My goal is to make an informed decision and set myself up to be a responsible owner. Thanks in advance.