Really, it's not. Depends on how you define "better" but all the semantics aside, a cheap BIC lighter is very reliable, helluva easier to use and loads more effective than any flint, ferro rod or spark-throwing gizmo. And if a BIC lighter fails or you happen to lose it (neither has happened to me in my 20 or so years of "weekend warrior" bushcrafting) you could as well carry a spare. Possibly wrapped in a waterproof package so you can pretty much guarantee it will work when you need it. And it's still going to cost about 90% less than a sparker/ferro rod at about the same size and weight. So you're basically right about the Sparkie being a novelty item for the most part.

Frankly, most people couldn't even start a fire with a ferro rod under ideal conditions. Let alone on a rainy day when everything is soaking wet and you happen to be close to hypothermia. A lighter (gas or butane) is far more useful inasmuch as it produces an open flame. No need to look for proper tinder first, you can light some birch bark or reasonably dry kindling right away and have a decent fire going quickly.

IME, the ONLY advantage of the flint/ferro rod/magnesium fire starter is reliability. Those things will throw a spark even when wet and they tend to be close to indestructible. To me, that's a good enough reason to carry one just in case (YMMV). A BIC lighter or even a Zippo will probably not light if you drop it in the water. Also, it will run out of fuel at some point. So aside from being a novelty item, a decent ferro rod or any other device working on the same principle can be viewed as a backup method. Which is only effective if you're proficient with it and carry proper tinder in a waterproof container as well.