Bitcoin core developers claim that Knots node operators exaggerate the statistics.

Golden Finance reported that this week Bitcoin Core developers erroneously claimed that nearly 40% of Knots Nodes, Core's biggest competitor, were being counted multiple times, creating a false impression of their actual scale. They cited technical criticisms regarding the number of reachable Nodes in Knots, accusing that (before many posts were deleted) as much as 39% of the Nodes (1,758 out of 4,468) were double-counted due to the so-called “Sybil attack”, thereby “artificially inflating the number of Knots users”. As background, the two most popular versions of Bitcoin node software are currently: Bitcoin Core (which accounts for approximately 80-88% of the market share) and Knots (which accounts for approximately 12-19% of the market share). The specific percentages depend on the estimation method.