No waveguide between lower directivity / wider dispersion. Waveguide means directivity matching at the crossover frequency at the expense of narrow dispersion.
eg. Two speakers with the same midwoofer.
Exhibit A: speaker with a waveguide-
relatively smooth around the crossover region. However, dispersion at high frequencies it relatively low- at 10Khz between the on axis at 70 degrees off axis the difference is 17dB.
View attachment 288431
Exhibit B: speaker with no waveguide: some directivity mismatch around the crossover region, but dispersion in high frequencies remains high- the difference between the on axis and 70 degrees off axis at 10Khz is 10dB better!
View attachment 288432
I find it odd that Dynaudio decided the Confidence 30 needed a waveguide despite their tweeter mating with a smaller 5.9" woofer, but the Confidence 20, mating with a 7.1" woofer didn't need one. That just seems like counterintuitive design. But your mileage may vary, perhaps you would be comfortable to buy a surround system with different design philosophy between speakers.
I mean, it would be hard to imagine a 5.9" woofer has worse directivity than a 7.1" driver, but who knows, maybe they just chose a really badly performing 5.9" woofer for some reason.