The other parts that can dissipate power are inductors, particularly those wound with very thin wire like you often see in less expensive (and some pricier) speakers.
That’s not a negative!! 🤣 The DCR (DC resistance) of an inductor can be effectively used as part of a circuit, especially a baffle-step compensation. Your average inductor has fabulous power dissipation capabilities (100W or more) so it’s a really good design choice when given a chance of using a low DCR coil and a big R or high DCR coil and no R I’ll take the latter.
So, don’t go willy-nilly reducing the DCR in a crossover unless you have measured what you are doing. In the even-ordered filter stages you would have to compensate for any missing R to ground with an additional R value.
This is where a crossover simulator like XSim or other can really help, as you can evaluate changing DCR in the frequency and impedance domain at the same time. Small changes in even ordered filter stages can have big implications in the minimum impedance.