There is a tool available to moderators that can show up to 1000 email addresses at once with a single query. On smaller sites, this tool is probably powerful enough to create a dump of the email addresses for a large part of the userbase with two dozen queries. And probably an almost full list of emails with a few hundred queries. I didn't run into any draconian rate limit on this tool so far, so I'm not sure what limits exist.
There are legitimate uses for this tool, but they don't require it to be as powerful as it is right now. A few tweaks would make this tool far, far harder to misuse for dumping large amounts of email addresses, returning far fewer results and limiting the minimum character count for queries would not affect the legitimate uses of this tool at all in my opinion. These tweaks would also make rate limits and alerts effective in stopping and detecting misuse of this tool.
We moderators aren't inherently trustworthy; in the end we're just random people on the internet. The tools that allow us to see PII should only be as powerful as necessary, and not more. And this tool is certainly far more powerful than it should be.
This tool might be even more problematic in combination with SO Teams, but as I'm not an SO mod I can't be fully sure about how all the tools interact with Teams (see my previous MSO post about that aspect).