| “what can be done without adding or reducing existing topology?”
Nothing.
It really depends on the situation whether the Triangle is bad or not. Triangles aren’t taboo! And they cannot always be avoided.
In non-deforming, flat surfaces they can do very little to no harm, as long as they are not directly at the edge of that flat surface.
On curved surfaces, they can cause pinching, when Subdivided, but even then you can sometimes get away with it.
