I encountered this for the first time today while attempting to read something on archive.today.
I confirmed that decoding the qrcode using a computer and following the URL it contains is insufficient; the error it gave directed me here which is what the linked screenshot is of.
The old type of captcha remains available too, for now:
OC writeup by @cypherpunks@lemmy.ml

What are the alternatives if one wants to read paywalled articles?
I would use archive.org. A quick internet search also lead me to the following website, which I have not tested: https://byebyepaywall.com/en/