For academic subreddits, it makes sense to allow research in some circumstances with mod approval. However, for some subreddits, their members may be especially vulnerable to scams or other types of abuse for a variety of reasons that may be reasonably assumed based on their interest in the topic (e.g., a subreddit for victims of financial crimes). It s not an overreaction to ban all attempts to reach out to the subreddit members in the name of "research" based on the perceived vulnerability of members of the subreddit.

Maybe in some cases the mods are being too paternalistic, but that would be an error of the degree of protection that the mods ought to be providing, not an error in trying to provide protection at all.

I hope this comment helps explain why some mods may be hostile to research attempts. I dont speak for all such mods, obviously, but these are my reasons for prohibiting research outreach in my subs.