It really depends. Get a hold of XSim crossover simulator or other such device.
The big power wasters isn’t the frequency filters but the equalizer and amplitude leveling resistors.
Look at it this way. Almost all multi-way speaker systems use drivers with drivers that don’t exactly have the same sensitivity to the amp signal. That is, for the same signal a tweeter may be at 96 dB but the woofer at 88 dB.
The only way to equalize these is to "pad" the tweeter level down so it’s at the same relative output given the same amp input. That’s where the power wasting is mostly concentrated, but Zobel, notch filters, baffle step, impedance compensation, etc. can also waste power as heat. This is also why you see such large cement resistors in crossovers. 5W resistors are typical, while 25W resistors are also possible. That’s all wasted heat. BTW, resistors are not the only place where power waste can occur, but they are the most obvious.
This is one area where active crossovers are undeniably better. Amplitude matching in the signal domain takes microwatts.