Here's a thought to ponder
It may be interesting to watch the US detergent market in the next year or two. Powdered detergents indeed are vanishing on store shelves, but I think some will remain for a while to satisfy a few consumers who don't like liguids.
BUT, an ever-growing factor in these markets is going to become freight/transportation if it hasn't already. Shipping heavy liquids around in big plastic bottles is going to become more and more expensive with prices of plastic resins and fuel increasing.
Since squared-off boxes (most powders) are most space efficient and they seem to weigh less per load, I think powder MAY get a reprieve as it becomes cheaper, relatively speaking, to move it to market.
I have recently been told that powders are easier on machines, mechanically speaking, especially on seals. That makes sense as at least in the original and 1st generation ultra liquids, the formulas often contained alcohol, which can dry out rubber. I have a good bit of liquid, but am going to switch back to powder when it's gone, at least while I can.