From the responses I've had from them via my distributor, they seem accustomed to having to hand-hold people developing with them ( maybe if their datasheets were better..!) , and hence can be reluctant to deal with smaller buyers - they sell in gazillions to LED video panel manufacturers.
Whenever I've enquired about data or pricing on new parts, they want to know details of the application to check suitability - last time I told them what column drivers (TI and MB) I was looking at using with their high-side switches, they initially came back saying those drivers couldn't be used in my application. When I emailed back pics of working prototypes they shut up & just sent the data & pricing!
IME there can be subtle differences between apparently similar parts ( e.g. the LE to latch data being on the last word, or an additional dummy one afterwards), and in one case making a significant functional change between revs of the same part.
On the other hand they are typically much cheaper than TI, so worth a bit of effort to understand.
TI can also be almost as bad though - just look at the LP5890 datasheet, with poor English and many barely-documented registers.