More like "people flying airlines based in English-speaking countries are more likely to generate trip reports based in English, given a higher likelihood of them being native English speakers". Nothing sinister, just a simple correlation of geography and native language.

I would also note that CX/BA F are relatively easy to come by as partner redemptions compared to counterparts in *A like SQ F, LH F and LX F (though that is seemingly changing with CX). The only partner redemption of those three "A airlines is LH, and that's only within a T-14 window, which is great if you're a college student who can fly at a whim, perhaps not so great when you have kids/jobs/desire to plan your travel somewhat in advance. SQ R is available via Chase MR/manufactured spend, but it's still a limited window compared to partner availability.

ST gives you even less- AF, KE and CZ, completely inaccessible for F redemptions from partners like DL and AS (though thanks to manufactured spend and Chase/AMEX, not completely inaccessible, just less so). And we all know the aspirational trip report relies on plenty of caviar, Krug and F, right?

FWIW, LX F trip reports started dying off once they essentially limited LX F to Senator or greater redemptions out of M&M... though I would imagine Vielfliegertreff.de still generates them, and we'll still get some because FT is a pretty large international community (that still skews to speaking English and the USA, though).