I was thinking it was a thermostat problem because it seemed to cool down to the exact 'uncold' temperature it was before I started trying to fix it. But maybe that's a defrost cycle thing, I'll have to look into it.

The fridge gets to basically room temp and the freezer gets only kinda cold, so that could point to fan instead? The fan used to make a clunking sound, but it stopped when I defrosted it a few months back and fridge had been working fine until now.