This claim had no article linked to it. However, I found an article to support this claim by The Guardian titled “Trees and land absorbed almost no CO2 last year. Is nature’s carbon sink failing?” which could be used to back the claim. This article argues that as earth's temperature increases due to climate change, it makes it harder for plants to absorb carbon dioxide. This is due to the plants and soil carbon uptake capacity weakening and becoming more and more fragile.
An article written by the Conservation International wrote in response to The Guardian's claim. The Conservation International argues that nature is still absorbing a large proportion of yearly carbon emissions, but recent human-caused stressors have damaged the net balance between absorption and emissions. Human interference such as deforestation, fires, and technological advancements, have decreased our ecosystem's way to perform to its best ability, but it's still performing the ways it is supposed to.
According to the Columbia Climate School, the percentage of CO2 admissions have risen steadily with the popularization of carbon dioxide fertilization. But this hasn't stopped plants from absorbing CO2, in fact, there have been some found benefits. Above ground plant growth has grown 21%, while underground plant growth has grown 28%, and crops such as soybeans, wheat, and rice are all expected to have better growing seasons. Another benefit to this is that “Under elevated CO2 concentrations, plants use less water during photosynthesis”. While this article in particular doesn't look specifically at how much CO2 plants and trees are absorbing, it does support the fact that there has been no negative effects on co2 absorption from plants.
https://www.theguardian.com/environment/2024/oct/14/nature-carbon-sink-collapse-global-heating-models-emissions-targets-evidence-aoe
https://www.conservation.org/blog/is-nature-failing-to-curb-climate-change-not-quite