Ads on the FB & goog network (this includes phys.org btw) are NOT paper tigers, in the sense that

  they are a reliable anti-signal

(to short, not to buy, to look at rising competitors, to look into reasons why a product might be failing, to sus out the lack of foresight in their investors, to extract other high cost channels/signals that they are still using ntless

As an example of the last one, I just learnt about an ISO standard.. )

YMMV depending on how much the network knows [it doesn't know] about you ofc ;)