The site's wording quantifies over every $n$ and is false for $3\le n\le6$. The smallest failure is $n=3$: a $2$-coloring of $K_3$ that is not monochromatic has no monochromatic triangle, so all three edges lie in none, and $3>9/4$. For every $n$, Theorem 1.1 (Keevash and Sudakov 2004) of Keevash and Sudakov [KeSu04] (p. 42) gives the maximum number of such edges exactly: $\binom n2$ for $n\le5$, $10$ for $n=6$ and $\lfloor n^2/4\rfloor$ for $n\ge7$. So the wording fails at $n=3,4,5,6$ ($3$, $6$, $10$ and $10$ edges against $9/4$, $4$, $25/4$ and $9$) and holds for every other $n$ ($n\le2$ trivially); the site's commentary prints the same three values. The change appends Erdős's words "for large $n$", that is, for every $n$ beyond some threshold; nothing else changes. The evidence is Erdős's own statement in [Er97d], item 10, printed p. 84 (item 10): "Rousseau, Schelp and I proved that if we color the edges of $K(n)$ by two colors then the number of edges which do not occur in a monochromatic triangle is at most $n^2/4$ for large $n$." The defect is the site's: its only source key states the bound for large $n$, and the site's wording drops the qualifier. The range $n\ge7$ of Theorem 1.1 is a theorem's range and is not used as the form. The one published result about the site's wording is the small-$n$ part of the same Theorem 1.1 (Keevash and Sudakov, J. Combin. Theory Ser. B 90 (2004), 41--53, doi:10.1016/S0095-8956(03)00075-3), which refutes it at $n=3,4,5,6$; it is credited here and counts for nothing. The site's label describes the corrected Statement, and the standing judges it.