You’re correct on both counts. The intent of the circuit in Figure 3.2 is to simplify the control slightly by reducing the number of required control lines, and allowing for a single PWM line. Nothing is preventing shoot-through if A and B are enabled at the same time, so care still needs to be taken when using that circuit.

A long time ago, when it was harder to source microcontrollers with a high pin-count in the hobby world, controlling motors with as few pins as possible was important to save the few pins available for other important uses, however ultimately this reduced the functionality and flexibility of controlling motors.

Nowadays, it’s easier to get larger microcontrollers with enough pins that such a circuit is not required. To be honest, on most of my H-bridges nowadays, I control each MOSFET individually, with it’s own pin from the microcontroller. This allows me to be much more creative in firmware with how I control the H-bridge, allowing for more advanced control than would be possible with the circuit in Figure 3-2.

Hopefully that makes sense, it’s been a long day at work and my brain is shutting down.

Cheers,
Roko

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