Note the final sentence of this paragraph outlined by Zeke (after the highlight). The authors were identifying how it wasn’t just high-end of range emissions-forcings outcomes in CMIP6 which had become “implausible”, but also that some low-end trajectories in CMIP6 have also now been surpassed.
Thats certainly a take. Here is what the new paper introducing the emissions scenarios we are using in the upcoming IPCC 7th Assessment Report actually says: