The post you commented on was talking about Toyota hybrids though, who don't use a CVT in the sense you're talking about.
They use a series-parallel hybrid transmission which is sometimes called eCVT, but works completely different from a classic CVT. There are no pullies, belts, chains, none of that. What they do have is a couple of motor-generators and a differential to link the system up with the engine and the drive shaft. No friction losses like CTVs have.
Ah, totally fair in that this particular transmission is better than the belt driven CVT stuff. I had thought they were still a bit worse than other transmissions, but it looks like if they are, it is on the order of 1% or so.
They use a series-parallel hybrid transmission which is sometimes called eCVT, but works completely different from a classic CVT. There are no pullies, belts, chains, none of that. What they do have is a couple of motor-generators and a differential to link the system up with the engine and the drive shaft. No friction losses like CTVs have.
See https://prius.ecrostech.com/original/PriusFrames.htm, or look up "Hybrid Synergy Drive" on Wikipedia or Youtube or your favorite search engine.