Q.Pothos
I have a lovely Pothos which has grown exceedingly long. In the process, it has lost leaves long sections of its stem. Is there any way of getting the plant to regenerate new leaves along these defoliated sections?

No, the stems will not generate new leafs in open sections.
Keeping the plant pruned will help you retain a full and lush plant.
Here are some links to help you.
https://www.gardeningknowhow.com/houseplants/pothos/pothos-plant-care.htm
https://www.gardeningknowhow.com/houseplants/pothos/propagating-pothos.htm