If that doesn’t sound bad, then its worse. No plants = no animals.
Normally we migt be shocked to hear that 20% of mammals face extinction, even though they tend to be less resilient than plants. Hearing that 20% of plants are at risk is a loud warning – that kind of hole in the food web could disrupt nature in a season or two.
Don’t put it down to sensationalism by the IUCN – there is no time for sensationalism. It is just a depressing legacy that we are responsible for this degradation of nature, this hole in life.