Ios Monterey: printing of a PDF doc included in mail not possible

You are looking for a feature in Apple Mail on Monterey that does not exist for attached documents. You can right-click on the attached PDF and choose Open With > Preview, from where you can print the now-opened, attached PDF.

What happens exactly? A pdf in mail is attached, is a separate file. You should be able to save it, open, print, UNLESS that specific pdf was created so as to disallow printing. In that case, the fact that it comes in a mail message is irrelevant, it is just how the pdf itself was created.

We are fellow users and have no insight into what happens within the Apple Mail product team. They do not participate in the Apple discussions community so there won't be a response to your "why Apple changed this…" question. Suffice to say it is their licensed product and they can (and do) whatever they please with it, regardless of how it impacts end users.

does it print if you save it to the download folder and then open the file from there with preview and print it from preview?