can someone explain to this mechanically stupid v rider why our bikes need TBS but cars don't?
Because most cars feed the cylinder intakes from a manifold branching from a single throttle body or carb. Most bikes have a carb or throttle body for each cylinder for higher performance. There are exceptions to each case.
The latest one really doesn't. There's just a single air balance adjust, I suspect it seldom needs touching.
cage FI is more sophisticated and ususally has a mass air flow (MAF) sensor(s)