I will never understand the utility of posting slides from a talk online without the audio.

One of the main reasons I come to HN is to learn how other people feel about certain things, predominantly from the comments section. Else it's just me in my cave.

It's obvious what point the slides were making.

The important part is that it said enough to inspire discussion and that it's qualified by its recency (posted last month) and by the experience of the person that gave the talk (front-end guy at Box).

It's useful for those that attended the talks. You generally don't need the audio, but just the highlights from the slides.

I found the slides to be quite informative.

I agree, but I definitely see the grandparent's point. These slide decks are annoying as hell. They're inconvenient for quoting, reading on-the-go, and they can leave out a whole lot of context. This is a trend that really needs to go.