[DennisP]

It's not like the one comment is the only newsworthy thing that day. It's a big complicated world with so many important things happening that we can't possibly keep up. It'd be easy to fill up the news with a tiny fraction of them, instead of picking one or two facts and spouting lots of opinions about them. Doing the latter is just a choice they've made.

[ElevenLathe]

Reporting novel facts is expensive. You need a travel budget, a widely-dispersed bureau network, a good research department, highly motivated journalists, and the list goes on. Opinions about existing facts are much cheaper to produce.