I've noticed, and I'm sure others as well, that speaker types tend to have characteristic sounds, which might broadly be divided into dynamic, horn, planar magnetic, ribbon, and electrostatic, with some esoteric technologies like plasmas in their own categories. That's hardly surprising since the designs tend to be constrained in different ways. Forex, all planars lack enclosure resonances, which lend all but the best boxes a "boxy" quality. Dipoles interact very differently with the room than monopoles (actually monopole/cardiods, since the radiation pattern changes with frequency). Line sources very differently from point sources. Electrostatics tend to be very fast and have extremely low distortion at moderate levels; they're more revealing of sources than anything except plasma. Ribbons and then planars tend to follow in that regard. Stretched Mylar diaphragms have a "mylar sound" caused by traveling wave resonances within the diaphragm, while dynamics suffer from cone breakup. Etc., etc.
So anyway, I think you're right, there are pronounced family resemblances, although some of the less common designs can blur them, e.g., a dipole dynamic like Linkwitz's won't have box resonances and will interact with the room somewhat like a planar, a dynamic line source will have some of the characteristics of line source planars, etc.
