Well, don't like the "gunking" up of my washing machine's filter/sump area that seems to come from using mainly liquid detergents. However suppose that could be dealt with by using higher wash temps and or doing more powder washes in between.
However for some items find liquid detergent is better than powders. Also when I want or need to wash in cool or cold water, liquids are better, IMHO.
Liquids also leave things that are supposed to be "silky soft" that way without having to use fabric softeners.
Again as I've posted before, have soaked stained table linens totally clean using Tide "free and gentle" liquid and cool to lukewarm water. Using powders to soak means having to first mixing in warm water, then agitating for awhile to make sure hte stuff is well disloved, and even then one finds powder resiude at the bottom of the tub.
Just my two cents.
L.