Yes, that 2 seconds is especially problematic on narrow, twisty, rooted inclines at slow speeds!
I don’t recall seeing this issue in other assist levels. I’m usually going so fast in sport mode that my fingers are always at the ready for braking. A quick tap on the brakes activates the motor inhibitors.
You can also try spinning the pedals backwards 1/4 to 1/2 revolution to trigger the motor cutoff. I don’t find it to be a problem on my original Cross Current which admittedly only has half the power of the Hyper Fat. I think that the controller tuning has to compromise between responsiveness and feeling that delay to motor cutoff. I deal with lots of threats to my safety and I have a feeling that if the motor cutoff every time I stopped pedaling for 1/2 second the bike would feel annoyingly surgey.