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Possibly there is some bias in your meter to a small underexposure (say 1/3 stop), but I do not think it is a full stop under.
You do not have a sensor problem.
A) They seem dark, but I think the camera is doing the right thing, which is why we shoot Raw mode. (see #3).
B) The proper exposure is probably a half or 2/3 stop higher, which is why we use the HistoBlinkyMeter in Manual mode.
C) The meter is performing correctly. It is trying to turn everything into middle gray, which is what it's purpose in life is. That is why we shoot in Manual mode and adjust based on the HistoBlinkyMeter on the camera back.
Meters don't know what particular shades things are and so aims for middle gray. The birch trees: they are whiter than middle gray, but the meter can't know whether they should be like other trees and darker than middle gray or lighter. It doesn't even know they are trees. So it turns them into middle gray. The background is roughly the same tone and gets the same treatment.
The interior has very flat lighting, low contrast but is above middle gray. The meter is trying to turn the white walls into middle gray.
The bright outside light siding is dominating the reading and the camera is underexposing it to turn it into middle gray.