Reading through both that and IBM's site, I'm struggling to see how blockchain enables this in any way? Covid test and vaccine providers have to be trusted for

Reading through both that and IBM's site, I'm struggling to see how blockchain enables this in any way? Covid test and vaccine providers have to be trusted for any of that to work, and without the "trustless" element blockchain provides you literally zero advantages (with a huge amount of disadvantages). EDIT: I guess I could request the whitepaper from IBM and read it, I mean what's yet one more tech giant sending me spam and selling my info to advertisers going to hurt? But I don't see any way for the entire thing to work and avoid people making up fraudulent test results/vax records without trust. I mean even with trust a clinic could feasibly fake that stuff, but without trust pretty much anyone could do it. EDIT2: Requested the whitepaper from IBM and it's literally just an 11 page marketing PowerPoint. Mentions blockchain a few times but doesn't explain how it solves anything that a normal RDBMS (or even some fancy distributed one with immutable records etc. where all parties are trusted) couldn't do.