I didn't read the post as a criticism of the community but rather a criticism of the technical workings of the site. Which is correct, HN is lacking a lot of things that make even the most basic modern forums more user friendly. The site performs poorly on mobile, you can't collapse comment threads, the reply button disappears sometimes unless you click "link", etc.
Also, HN has dramatically increased in quality over the past 6-10 months. It's been very noticeable for someone who's been here for 4 years.
Can HN be an echo chamber? Yes, at times. But much less than other online fora that I've participated in (most Reddits are 1000x worse, for example)
Does the site design itself leave a bit to be desired? Maybe, but I've grown quite fond of it.
And what exactly "empty promises" are you talking about?