Looks like 64x64 matrix, probably 64 anode-connections on 1 side and 64 cathode connections on the other. I would expect a lot of flicker with 64:1 multiplexing at 1Khz; that's basically 16Hz flicker-rate.
Even the 128x32 dot-matrix displays used on pinball machines have annoying flicker in my opinion. So, scan-in 64 cathode values, turn-on anode #1, turn-off scan -in next 64 cathode values, turn-on anode #2, etc.
Alternating green and orange suggests there is phosphor, rather than gas, to set the color. That would be another wearout mechanism in-addition to sputtering and gas-leaks.
I have to say, the Soviets sure spent a lot of time developing high-voltage display technologies, and seemed to lag developing LCD which was already outpacing LED in many US applications by 1980.