It seems that HN has a lot of anti-user features for the sake of it. Perhaps the rationale for graying out self posts is to make them not stand out (so that the post from OP doesn't get any undue advantage over the comments), but it's just an accessibility nightmare. It's as if people with poor eyesight were not welcome here.
In some cases I agree, but in this case it might be that making the top text darker would contrast too grossly with the bright white background of the textbox below, making it painful. I actually think it's rather balanced.
It could also be observing the necessary humility of offering a submission to be judged and engaged with by the larger community. In this community "light slate gray", or thereabouts, is the "Hessian sack of humility".
That fact that my mid-20s eyes still require having HN at 110% zoom should be a clear sign that design is not a top priority for the site. It's fine, you can always do custom CSS, right /s
I do that too. Only needed to once I went from a (1080p) 27" monitor to a 24" one.
Not required, but the size at 110% looks better to me. Recently discovered that firefox saves this value if you do it outside of a private browsing window, prior to which I did it on each browser restart.
I use Refined Hacker News https://github.com/plibither8/refined-hacker-news which alleviates some pain points, but unfortunately it doesn't fix this issue.