First of all, detergent pods are for dummies who cannot measure the right amount of detergent for a job and those who don’t know that water hardness is a factor. They are for convenience zombies who cannot be bothered to think. So from the very start, pods are not for solarpunks.
Someone told me they had a problem with their dishwasher because undisolved gelatin sacs were gumming up their drain. The linked article goes into clogs. This article (if you can get past the enshitification) says there is research on an environmental impact by pod sacks. So that’s also antithetical to solarpunkness.
So do it right. Fuck pods. They cost more anyway. Buy powdered detergent if you have soft water (or if your dishwasher has a built-in water softener) and use less (to avoid etching). If you have hard water, either use liquid detergent or just use a bigger dose of powder.
I think liquids are heavier to transport than solids because solid detergent is more concentrated (no water). Liquid detergent (which comes in all viscocities) still has its place: for people with hard water. But apart from that I think solid detergent is the best for the environment.
There are those solid tablets which are like powder pressed together. Sometimes those are in a plastic wrapper that needs to be removed before use (yikes), and sometimes they are in a disolving gelatin like the liquid pods. But I guess the sacks of powder need not be as thick as the liquid ones.