If you have a digital crossover, you can easily modify crossover characteristics with a simple programming change. That's nice for hobbyists that modify speakers a lot. Analog crossovers can be changed too, but that requires a component change, or sometimes a jumper change. Analog crossovers aren't usually as versatile because changing filter characteristics requires component changes. But in either case, don't underestimate the value of a good crossover. Designing proper filter characteristics for matching loudspeaker subsystems is not a trivial matter. Summing through the overlapping band is affected by electrical, mechanical and acoustic properties and getting it all correct takes a lot of work, particularly when considering directivity for best on and off axis response. That's important because the total reverberent field is what you hear, and that includes off-axis energy as well as on axis response.