lol - that's exactly what i meant. 60-70mm is what I run my replicator clone at and the print carriage for that is carrying 2 direct drive extruders - it's a heavy lump.
60-70mm/s is S-L-O-W.
My cheapo ctc ACTUAL prusa design (design, not bits, the ctc bits are cheaper than chips) will happily chug along at 200mm/s - with dimensional accuracy.

The point is that the original prusa design is nmeant to be a machine that can print both fast and accurately.
And that's what creality took away when they decided to cripple it for the sake of about $20: One stepper motor, 3 smooth rods, 4 bearings and a lead screw. That's all that lies between a really good i3 and most of what creality currently make.
With the cr series it's even less. Just the stepper motor, leadscrew one smooth rod and throwing away the ridiculous bowden setup.

And the things is the prusa design is open source, you don't even need to design anything it's all free to download.

Maybe the chinese are so used to ripping off copyright that it never opccured to them that they didn't need to change anything.
Who knows.

But at the end of the day if you built a cr10s with the added extras then it would print 2-3x faster and just as accurately. The frames are rock solid.