If they had an electrolyte that worked in this application they wouldn't be talking about all the possible choices. They would tell us what worked.
"For this solid electrolyte, we have plenty of choices. We can use gelled polymer electrolytes, made by swelling a polymer matrix with an electrolyte solution, or we can solidify ionic liquids by adding polymers or silica nanopowder. This nonleaking design, together with a virtually unlimited number of charge and discharge cycles, means that our supermicrocapacitors will likely outlast all other electronic devices on the chip. Such long life will be particularly useful whenever it is inconvenient or dangerous to open things up to replace a power source, as in pacemakers, defibrillators, and other medical implants."
Electrical and magnet fields occur in 3 dimensions, not one. They can talk about the gap between the fingers of their layout, but their effective average gap in 3D is probably closer to PI*center_distance/2 which gives a lesser result for the expected capacitance. Their max voltage with a given electrolyte is limited to the closest edge, but that is not how a physicist would compute expected capacitance.
The life of a repo man is always intense.