I've gotten what seems like a lot of similar email offers lately, plus constant chatty updates I don't recall signing up for from Canva and other places I know I have accounts with. BookBub seems to want terribly to Be My Friend, which is absurd, since they have a long line of people desperate to pay them thousands of dollars every day. Yes, in theory I could turn off all notifications, but FOMO (fear of missing out) makes me just leave the email in my Inbox, to read through Some Other Time. Or never. These kinds of emails promise to teach me something I don't already know about marketing and promotion. About 99% of the time, that's not the case. Canva, sure. Alli? WhatshernamePenn? IngramSpark newsletter? Nope.
Some people soliciting business from me are the same people I've dealt with before, but they've split off into multiple names. So at first I wonder, "Who is this?"
As far as new-to-me promotion companies doing the equivalent of an email cold call, my answer is to delete. It's too much work to research whether they are legit or effective for other people's books. And since well-known companies like ENT haven't been effective for my own books, what's the point?