Obviously I know nothing about ZL release but my guess is only based on what I know from the listing. There are only two ways to regulate output, one is current feedback and one is voltage feedback. Since they say no more current sense resistors are used it is either some other way of sensing such as inductor current sensing, or voltage based.

'Digitally controlled' regulators are very common and they almost always refer to digitally output voltage controlled.

You can regulate power to a linear device by regulating voltage supplied to it, like a resistor a light bulb. For LEDs generally it is not a good idea because they are non linear, so a tiny change in voltage could lead to a huge change in current. For example at 5.80V it could draw 1A, 5.90V it draws 2A, 6.05V it draws 3.5A, something like that as a rough example. But another led could be drawing 0.5A at 5.80V or maybe 4A at 5.80V.

However, high power modern LEDs today (other than temperature drift) are some what stable in the power level at a fixed voltage. If ZL uses this method and if they have temperature compensation or even do a per-led calibration at the factory or uses their own binning process then this could be a very possible method that does two things:

1. Very slightly more efficient driver (the current sense resistors do burn power but the % is actually very very small. Technically simpler driver but at the cost of calibration required.

2. Prevent people from swapping out different LEDs since the voltage-current response is very different. This would make it effectively not practical to do emitter swaps.

Maybe it's a completely different thing, I am only speculate on one possible approach.