it means that the product that is talked about but not named, is better then the one commonly used.
in·cum·bent
inˈkəmbənt/Submit
adjective
1.
necessary for (someone) as a duty or responsibility.
"it is incumbent on all decent people to concentrate on destroying this evil"
synonyms: necessary for one to, essential that, required that, imperative that; More
2.
(of an official or regime) currently holding office.
"the incumbent president had been defeated"
synonyms: current, present, in office, in power; reigning
"the incumbent president"
noun
1.
the holder of an office or post.
synonyms: holder, bearer, occupant
"the first incumbent of the post"
it is referring to whatever product that is not named, but that is dominating the market, but inferior the new product" the "your product"
hope that makes sense