No, we need the diversity. Healthy competition promotes better software, and is ultimately better for the end user. Being the single "best" at something promotes complacency. Simplify 3d is sometimes seen as an example of this; it *was* clearly the best slicer option a year or so ago. (ducks for cover for the ensuing fanboy war)
We look at quite a few other slicers & 3D printers to see what they did well / bad. So having some competition is a good thing, even though it does mean that certain things get re-implemented.
In some cases it's even good that something gets re-implemented, because you can occasionally find a much better way of doing the same thing. Improving on something that's already there tends to suffer from moving towards a local maximum.