Posting this because the summary going around does not say what the paper says, and the difference matters for how people here are using it.
The trade-off is reversibility against privacy and there is no option that gives you both. Card payments are reversible and disclose the most; crypto discloses least and is irreversible, which is precisely why pressure toward it is a warning sign when it comes from a seller rather than a buyer. Escrow only means anything where the escrow agent is independent of both parties, which is rarely the case in practice.
Where I think it is weakest: the follow-up is short relative to how long people actually take these drugs, so durability is an assumption here rather than a finding.
So the question, as narrowly as I can put it: how people are thinking about the trade-off between reversibility and privacy, because you cannot have both. I have searched first, so if this is covered somewhere point me at it and I will read it.
Note on sourcing:
Figures above are from the primary publication rather than the press summary. If a number here disagrees with one you have, post yours and we will work out which of us is reading a secondary source.