Those are a lot more valuable (and seem to have more activity) than most of the other threads there.

Of the 25 non-sticky threads currently on the first page, 6 are about SIMs.

Of the remaining 19 threads, I'd say that at least 5 of them aren't related to travel technology.

It's a travel site, so even if they were dominating the tech forum (they aren't), it shouldn't be unexpected as the topic is one of the few legit travel related tech discussions actually happening