There are lots of different studies for different vaccines, variants, and criteria.
I believe the article above showed that it was 60% if you only were
partially vaccinated, i.e. one dose of the two-dose vaccines. Not that it slipped to 60% if fully vaccinated.
That is problematic for countries that relied heavily on one-dose, based on the idea that the first dose protected enough - and the second was only needed to make the protection last longer.
For the Delta-variant it's worse it may be as low as 33% for AstraZeneca according to:
https://www.gavi.org/vaccineswork/fi...-we-still-need
However, two weeks after 2nd dose (i.e. fully vaccinated):
Pfizer/BioNTech (against infection): Original 95%, Alpha 92%, Delta 79%.
Pfizer/BioNTech (against symptomatic): Original 95?%, Alpha 93%, Delta 88%.
AstraZeneca (against symptomatic): Original ? (90%?), Alpha 74% Delta 64%
AstraZeneca (against hospitalization): Delta 92%.
All of the numbers have some margin of error, and they are not fully comparable as the different vaccines were given to different groups, and you don't know if different studies use the exact same criteria for symptomatic infection.
Obviously the fact that a single dose of AZ doesn't protect well against Delta raises the issue that the Janssen (or J&J) vaccine might also struggle - but it seems it actually works.
https://edition.cnn.com/2021/07/01/h...ant/index.html
Or in summary: the FDA/EMA almost-accepted vaccines work when you are fully vaccinated - even against variants (except AZ against Beta - which is the South African variant, Alpha is from Kent, uk, Delta from India). Not perfectly, but quite well.