I imagine there are others. The older Tek probes even had ports to refill with now-banned chemicals. The newer ones don't, but are more expensive. Frequency response is a significant concern. Designing and manufacturing a decent HV probe is definitely non-trivial if you need flat frequency response.
Many parts have significant voltage coefficients, too, as well as breakdown voltages.
This isn't easy. This shield acts as a capacitance to ground for the HV resistor, routing some of the high-frequency current which is supposed to go to the output, to ground. Most solutions can just as easily cause a region with a response hump, as well as a dip, or even both. BTW, these problems are much harder if one seeks to make a probe with very low capacitive loading and high frequency response. The Tek P6015A probe is 3pF, and you'll also note it has a veritable raft of response adjustments on the scope-input end.