I have a 2019 SR+ Model 3 with about 60K miles on it that I have owned since new. I charge it almost exclusively in my garage with a 240(? dryer style) outlet using TESLA's standard charging cord that came with the car, and for the last 4 years it has charged consistently at about 32-33 MPH. It may be coincidental, but once the car updated the software to 2023.20.8 a few weeks ago, it immediately began defaulting to a 15amp charge speed every time I plug it in. I discovered how to override that manually by bumping it up to 32 amps either on the car screen or using the app. Once I manually bump it up to 32 amps it remains there until the car is fully charged then it reverts back to a "15 amp" charge. I have to manually reset it to 32 amps every time I plug in the car. It has NEVER done this over 4 years and 60,000 miles of charging, 95% of which is done in my garage with the same charging equipment.