Your message to xxxxx was not delivered because this mailbox does not accept mail from the Gmail system. Gmail not only invades the privacy of its users, but of their correspondents. Please re-send using another service, or call or write.This is an interesting approach to Google privacy issues. It assumes that other email systems don't glean information from users the way Google does. I'm not sure we know that to be true.
Unlike those old anti-spam systems that asked the sender to type a confirmation, this is just a block. Unless it's a simple auto-reply, written to appear to be a block, as a kind of protest against Google, while the email is actually received, and possibly kill-filed into trash.
Either way, this person isn't too concerned with receiving email. All my email accounts are through Gmail. I have email at both my workplaces, but I don't use them for personal matters. And I'm certainly not opening an email account from some other company to correspond with this person I don't even know.
The reader gave no phone number. Not that I would call, but her auto-reply suggests that option.
And she's asking me for a favour.