I think you either severely overestimate the capabilities of a C64 or underestimate what it takes to put a modern user interface experience together. The C64 h

I think you either severely overestimate the capabilities of a C64 or underestimate what it takes to put a modern user interface experience together. The C64 had a resolution of 320x200 pixels with 16 colors. That would cover about 1,5 square inches on a modern phone (modulo the colors, another factor of 6 to 10). You could not dream of re-rendering the whole screen with any FPS number. Games had to resort to all kind of tricks to create a smooth experience, and whatever was put on screen was pre-rendered content combined in clever ways. Calculations involving floating point like a mandelbrot set in said resolution took hours to days per _frame_.