I've recently started hearing phrases like that despite technology X existing. What has changed recently that people have become so ignorant?
Have you ever thought of where all those fossil fuels came from? They had to be captured by plants without emitting more CO2 than they captured. The bigger problem with industrial CO2 capturing processes is that they merely capture it, they still have to store them for millions of years just like plants did when they were turned into coal or oil.
The energy requirements of sequestration processes may be significant. In one paper, sequestration consumed 25% of the plant's rated 600-megawatt output capacity. After adding CO2 capture and compression, the capacity of the coal-fired power plant is reduced to 457 MW.
https://en.wikipedia.org/wiki/Carbon_capture_and_storage#Ene...
You can even use it to pump more oil!
In carbon capture and sequestration enhanced oil recovery (CCS EOR), carbon dioxide is injected into an oil field to recover oil that is often never recovered using more traditional methods.
https://en.wikipedia.org/wiki/Carbon_capture_and_storage#Enh...
Of course it does, if the price of CO2 is high enough. If I can capture 1.1 unit of CO2 per unit of CO2 released and it still makes me money, I'll use any energy available. This could happen if e.g. the government subsidizes carbon capture credits or simply if an efficient enough process exists.
On top of that, if the price is high enough it would be viable to build renewable energy solely for powering carbon capture.