Strangers just wanting to sell you a dog????? Isn't that EXACTLY what she's asking for??? By implying that someone who PM's them that the person would automatically be non-legit is misleading and untrue. You do more harm than good by making unfounded statements.
Here it is: I live in Washington state (so obviously I'm not trying to sell this person). I have exceptionally nice, well breed, of exceptional health & quality, championed sired/championed dam/ champion grandparents, et al puppies for sale. Anyone in the northwest that posts they are looking for a puppy I will PM them...for no other reason than they (by posting their location and interest in buying a puppy) have essentially requested an interest and in so many words requested I do so.
I have no desire to announce to the entire forum (though I realize I just did, but only out of necessity to stop this ridiculous "warning" and unfounded junk talk to people), so I will let those in my locale -who have specifically requested to buy a puppy know though PM that I may - or may not - have a pup that would fulfill their need/want. - guess what? I don't ship to NY, etc...so there is no reason to let the whole forum know I have puppies available. Just from minor postings I've already had so many contact wanting me to ship, etc. The seller has the right to selective posting of puppy availability.
So for heaven's sake quite telling people looking for a pup such junk that if someone PM's that person couldn't be legitimate. I don't sell to just anyone either - the potential buyer would have to meet my expectations just as much as I should meet theirs. But that is between buyer and seller and not the entire forum. And I am also acquainted with another breeder who breeds exceptional pups, thus if I can't meet a local person's need I could refer the person...who, in the end, makes the final decision whether I or another breeder is right for them.
It is one thing to state, "be careful of PM as there is the slight potential that one PMing might not be legit" which is much different from the implication that all who PM are not legit. Just please if you don't know what you're talking about and can't back it up with facts don't make wild generalized statements.