Some products — like devices powered by combustion engines, medical equipment, farming equipment, HVAC equipment, video game consoles, and energy storage systems — are excluded from Oregon’s rules entirely.
It's interesting to me that Game Consoles get an exception... Not sure whats up there, other than straight up bribery lobbying.
HVAC makes sense when you consider environmental concerns (some refrigerants are really terrible pollutants).
Medical equipment, particularly equipment in public health care should be held to high standards. Authorized, properly trained repair; peoples lives depend on it.
Energy storage when attached to public infrastructure (you back-feeding the grid) can be a saftey concern for workers and the supply/load needs to be balanced to prevent damaging that infrastructure and other private equipment attached to it. Not sure preventing repair is the right move here; you can still buy and install new without oversight. Perhaps it's again a saftey concern (for the person performing repair).
Vehicles, farming or otherwise, I'm on the fence about; there's an argument to be made for public saftey/roadworthness, but I'm not sure that's enough of an argument to prevent home-repair. Again seems more to do with lobbying than anything else.