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CRT screens did 75Hz/85Hz/100Hz quite well, but rendered only one pixel/dot at a time. This is in no way equivalent to 60Hz on a flat panel!

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It isn't equivelent in the sense that the progressive scanout on CRTs resulted in near-zero latency and with minimal image persistance, versus flat panels which are global refresh adding latency and worsening motion clarity. So it isn't really a "but", it's a "made even better by being rendered only one pixel/dot at a time".

Motion clarity yes, but it's zero latency in the least useful way possible, only true when you're rendering the top and bottom of the screen at different points in time. And scanout like that isn't unique to CRTs, many flat panels can do it too.

When rendering a full frame at once and then displaying it, a modern screen is not only able to be more consistent in timing, it might be able to display the full frame faster than a CRT. Let's say 60Hz, and the frame is rendered just in time to start displaying. A CRT will take 16 milliseconds to do scanout. But if you get a screen that supports Quick Frame Transport, it might send over the frame data in only 3 milliseconds, and have the entire thing displayed by millisecond 4.

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