Decaffeinated coffee plants, of course!

Good schtuff!

(decaffeinated) by extracting the caffeine from the green coffee beans. Various solvents are used including water, carbon dioxide or harsher chemicals such as methylene chloride. The beans are then dried and roasted. The roasting process is a little different according to our local coffee roaster but I don’t know the details of that.

...nobody is using chlorinated solvents anymore.
It used to be tge primary way, but that started shifting to water 35 to 40 years ago.
The last of the conversions happened in the 90s.
The CO2 process is expensive, but removes FAR less of the flavor components so is way, way closer to unadulterated coffee. But, we pay for it.
I don't drink decaf because I generally agree with you. It doesn't taste the same.

Caffeine is more soluble than any of the phenolics or esters that are the principal flavor components.
So, by extracting with cold water, they can remove the caffeine without drastically changing the test. (It still does lower the "richness". The process is far from perfect.
The used to use methylene chloride until the public started gaining awareness of the many issues around chlorinated solvents.
The industry converted en masse to water, but kicking & screaming.
Caffeine for stay awake tablets is still extracted from low quality coffee beans using solvents but usually something line methyl ethyl ketone, which is a safer solvent than methylene chloride.