EDIT: Some of this answer maybe still applies, but basically I seem to have misread the question. Apologies. HN has in fact changed quite a lot over the years

EDIT: Some of this answer maybe still applies, but basically I seem to have misread the question. Apologies. HN has in fact changed quite a lot over the years and PG has been visibly tweaking it continually. I guess you are asking specifically about why the graphic design has not changed much... Pretty clearly modernity per se is not worth optimizing for. I have zero inside knowledge, but some thoughts on what the current design might be optimizing: 1) HN probably benefits from discouraging undesired users in a variety of subtle ways. Like the trivial Metafilter subscription fee, an unadorned layout may create a low bar that discourages extremely casual users. PG is pretty explicitly NOT trying to rapidly scale HN. 2) The YC partners have a lot of opportunity costs for every hour of work. Current layout good enough? OK, on to the next problem... 3) Quick load times, works in any browser/OS/device. To answer your question with a question: what do you think could be functionally improved by a redesign?