Driving around in frigid weather from VA to MI and back in January showed the impact on the "traction battery." I'd reset the R4P's m/kWh and mpg indicators at the end of Dec 2023. That happened to be when the 30K service was due, which includes an oil change. I've driven about 3000 miles in the last month. The m/kWh is at 2.7, compared to 2.9/3.0 for Jun-Dec 2023. The mpg went down as low as 35 mpg when daytime temps were under 25, which lasted about a week. When I've driven up to Lake Placid and back during the summer, usually see about 38 mpg.
In short, living in NC having a PHEV makes more sense than if we lived in upstate NY or New England, or in Chicago where my husband grew up. Pretty sure his brother who stayed in the Chicago area has a hybrid.
When my daughter was checking out Subaru SUVs in Asheville, NC a few years ago (she was in college there), the dealership wasn't even carrying hybrids. That makes more sense to me now. The R4P is rated lower for mpg than the RAV4 Hybrid because is heavier due to the weight of the traction battery. Asheville is at 2000 ft in the mountains. Not that much colder in the winter but clearly colder than central NC.