However, as comedian Emily Heller points out, normally when you’re mass emailing a bunch of strangers, who also don’t necessarily know each other, the proper thing to do is blind copy them.
That way, everybody gets your email, but you haven’t broadcast the addresses of everybody to else to the entire mailing list.
This is totally fine, it’s part of the business.
Since Mia Dolan is doing all the work herself to promote her show she has to email all the media outlets and casting agents directly to try and get some attention for her show.