I also think the conclusion is suspect. But note that they are comparing “emissions”, not amount of fuel used. One would think they’d go hand-in-hand, but maybe not.

I wonder what the ratios of hybrids are. My in law has a hybrid SUV that barely gets better gas mileage than the equivalent gas model on the highway, which is most of their mileage. If the majority of hybrids are those, not Priuses, then I wouldn't be at all surprised if the extra materials from the battery and engine offset the extra 3-4 mpg gain.

Worse than something people don’t utilize? Im calling bullshit.

A regular hybrid is always using its ICE to charge its battery. A PHEV can either charge via the grid, or with its ICE.

The minority of people who do opt to mostly charge their PHEV via the grid and do not constantly take long distance trips are able to fully utilize a PHEV's advantages, and thus they help bring the overall average down for the PHEV category, but since there are so many more who do not, the average is still quite poor despite PHEVs having the real potential to be much better.

a non-PHEV hybrid, by not having the grid as an option, does not have the benefit of that mindful minority of people helping to bring the average down as much, thus it is worse than PHEV, but still better than ICE.

A regular hybrid still generally have reducd emissions compared to an ICE vehicle if used in an urban setting, and due to how small their ICE engines tend to be, they usually use less fuel even on long-distance trips compared to the average ICE vehicle.

The point of the study is not that they don't emit less than ICE vehicles, it is that, overall, due to how most people use them, they don't save all that much carbon over their lifetime compared to non-hybrid EVs (which, I will mention, also pale in comparison to public transport). And in the case of PHEV's, they could be used to great effect, but the majority of buyers appear to not do so, thus making them similar in carbon reduction to regular hybrids.

If you would rather not watch the video itself which goes over the studies and their conclusions, the creator provided sources to all the studies in the text description, which I will provide here for you to look through: