I’ve noticed that it’s much stronger when the ventilation is on - either AC or heat, compressor on or off, it doesn’t seem to matter…it is possible what you are smelling is mold in the HVAC ducts. The conditions are perfect this time of year for the mold to grow rapidly. Try replacing the cabin filter if equipped and spraying an entire can of Lysol in the filter opening with the blower on high. If the doors on your vehicle were bent to the point that they were not sealing properly then rain could have gotten into the cabin and then the sun could have turned it into a mold farm. It happens.
I am in a body shop every day and when a vehicle is complete I only occasionally get a whiff of new paint. Call a dedicated detail shop and see if they have a machine called an “ionizer”. When this machine is used for a couple of days, continuous, it just might do the trick if it is not to bad.
Wash the car all you want, provided you use mild soap and very clean rags/sponge. BUT, do not wax for 60-90 days so the paint can cure.