Reconciling V, A, iPF and kW for my air conditioner
No you can't assume that. A compressor is primarily a motor which will have a relatively steady current draw. The inverter may convert that to pulses, but a PFC inverter with power-factor correction would not.

But a motor has friction and requires lubrication. As the motor ages, friction will increase, and the viscosity of the lubricant changes with age and temperature. Also the load on the motor will change according to the work being done by the compressor - which is a function of the temperature on both sides.

The motor's ratings must take these factors and other variables into account. On another day, with different temperatures and a much older motor, you may find it's power is close to its rating.

All you can conclude is that today's measurements show a lower than rated power consumption.

If you need to test the power meter for accuracy, you'll need to test it with calibrated loads - both resistive, and non-linear, (such as a bridge rectifier, reservoir cap, and resistive load) not random pieces of equipment.