For a while, I considered buying the liquid stuff, because the powder wouldn’t always dissolve and then sticked to my clothes.

Using less powder certainly helped, but I also found out that it’s legal to dissolve the powder in water beforehand.
I just put some hot tap water and the powder into a glass jar, and give it a shake before I pour it into the washing machine.

I’ll tell you one difference that the article probably didn’t mention. If you get the liquid on your clothes and then go stand under a black light at a nightclub, you can see everywhere that the detergent touched, despite them having gone through a full wash cycle. I discovered that through experience, and felt humiliated. So, I immediately switched to powder and stuck with it.