B13 ABS is primitive and counterproductive.
I believe it is a 2-channel system, but the last time I tried to remember I think I got it wrong. A 2-channel system has the front-left tire and rear-right tied together so that if one slips, braking on both is modulated. Same goes for the opposite pair. That means if both front tires slip on a poor surface, you lose all rear braking too. And vice versa.
The G20 has a 3-channel system I believe? Where the front two tires are on individual channels, and the rear tires are on the third channel. This isn't great either, but at least a step up from the other system.
Modern cars obviously have a 4-channel system and even those don't have good ABS logic behind them sometimes.
The B13 ABS is a joke and IMO a safety hazard.
If we had a dedicated brake section, I could find the previous thread on this topic.

As it stands now I've been searching and I can't find it.