Smaller, cheap, RC helicopters generally have very pronounced twist in their blades, and also vary their chord - slightly larger, slightly more expensive RC helicopters have no visible twist or chord change in their blades (i also own both varieties, and the larger blades also have no measurable twist - the answer and comments to Why do helicopter rotors have constant section and angle of attack? posit that real helicopters have twist in their blades, so i was unsure whether it is only an optical illusion in RC helis)
The most expensive of all RC helicopters, Ingenuity, also has very visibly pronounced chord and angle changes, so it does not seem to be about price :-)
With the huge difference in airspeed over the inner versus the outer portion (In the example picture, the larger, yellow, helicopters innermost chord should only get less than a quarter of the airspeed that the outermost portion gets) i would expect a more visible twist - is this something that only happens in flight, as a reaction to aerodynamic forces, i.e. does the blade twist while in use? Does changing the chord as well as the aoa pose too big a construction hurdle for the bigger RC blades, while it is easy to do in injection molded plastic for the small ones?