Terminal Scan types your word onto a CRT with a bright scanning line sweeping down the display and a block cursor blinking at the end — a monitor being read, not text being animated.
ts-reveal exposes the text through a mask, ts-scan drives the sweep line down the frame on a separate slower cycle, and ts-cursor blinks the block at roughly the rate a real terminal does. The phosphor glow is feGaussianBlur and feMerge.
Typewriter is mechanical and paper-based — letters strike in with a caret. Terminal Scan is a lit screen: the scan line and phosphor glow are the whole point, and they have no mechanical equivalent.