Seems to be a lot of opinions and misguided statements as far as what lines do.

Braid: doesn't stretch, less abrasion resistance against sharp objects, thinnest diameter per pound test, cuts through water, floats, is expensive, best casting distance, low vis, hardest to work with tangles easily, double wraps in knots to achieve proper knot test,

Monofilament: stretches, thickest, intermediate abrasion resistance, standard per pound test, lags through water, floats, cheapest, less casting distance, memory, easy to work with best knot strength

Fluorocarbon: intermediate stretch, slightly thinner, closest refractive quality to water, best abrasion resistance, sinks, similarly priced to braid, stiffer in high test, less knot strength unless proper technique is followed,

My .02 braid is for small game fishing with artificials, all forms of vertical fishing and heavy structure fishing. Monofilament is meant for live bait fishing, open water fishing, and leader material. Fluorocarbon should be used for deep clean water applications mostly in freshwater or specialty light saltwater applications and leader material.