Of tire pressure and such...
I wish Subaru would go to non-sensors for TPMS like other manufacturers. Mazda doesnt have any sensors in the wheels on newer models and bases the TPMS off wheel speed vs. pressure. Makes it super easy for wheel swaps and no additional costs for separate sets of sensors.
I have a feeling that system wouldn't work quite as well on a Subaru, since it's real all-four wheel drive. The indirect sensors are not very accurate in comparison, and we already know that true AWD systems have very tiny tolerances for wheel size differences.
The pros of real AWD is that it's always on, always active, and in the case of our VDC, ABS, X-Mode SubieSystems, always responsive.
The cons are you must always rotate tires regularly to maintain tread depths to within 2/32" of an inch of each other. It's also why proper inflation is so very important on a Subaru and there will likely never be the current indirect system on a Subie (except maybe the BRZ?), even though they're cheaper.
Mazda cars and SUVs, Toyota cars and SUVs, many Hondas, and most VW cars and SUVs use a front wheel drive with rear wheel assist system, so, there's no 24/7 all the time impact to the driveline and differentials, because usually, only the front wheels are driven, or the front wheels are driven with 90% power. Nissan uses a 100% FWD system with very limited AWD at under 25mph with a button press to activate it.
We don't have the luxury of the cheaper, easier to work with, less accurate indirect sensors that others' use.

lain:
Neither do Porsches with real AWD.
https://tires.tirerack.com/tires/Tread Depth Subaru
https://www.edmunds.com/car-safety/tire-pressure-monitors-can-you-rely-on-them.html
The lower-cost, indirect TPMS doesn't actually monitor air pressure. Rather, the indirect TPMS uses the antilock braking system's wheel-speed sensor to detect that one tire is rotating faster than its mates. (An underinflated tire has a smaller circumference so it has to roll faster to keep up.) Thus, there's a large margin of error in indirect systems.
Meanwhile, a direct TPMS measures a tire's actual pressure. Such systems are usually accurate to within 1 psi. Current direct systems use a gauge mounted to the wheel or tire valve. This gauge sends a signal to the car's computer. How the data is interpreted and displayed in the car with a direct TPMS depends on whether it is a low-line or high-line unit.
A high-line system has sensors mounted in each of the wheelwells and displays the individual pressure of each tire on the instrument cluster. Low-line systems are found on less expensive cars and will only prompt the low-pressure warning light. It is then up to the driver to figure out which tire is low. Much more useful to drivers, clearly, are systems that actually display the pressure of each tire.