Research is all about studying topics of uncertain value. You have to commit to a project long before you can say if it's actually worth doing.
Taste comes with deliberate effort and experience. It doesn't tell you that a topic is definitely worth studying, but it increases the likelihood that you will guess right.
Either the reader already has it, in which case there’s no point in being told that. Or the reader doesn’t, in which case you have declared that good taste cannot be taught.
Perhaps the author’s next article should be How to win the lottery: be lucky which is just about as actionable.
I recall reading an interview about a legendary developer, and the majority of the interview was not focused on his coding decisions or the structures he built, but it was about a notebook that he kept with voluminous notes about what was good and what wasn't. That notebook is a materialized version of 'taste', and it's certainly something almost anyone could put together with enough effort and time.
> But if I had to summarize it in one sentence, it would be that taste comes from practicing the skill of research, keeping your focus always on identifying what works and what doesn't.
Instead of following general guidelines, focus on figuring out what works and what doesn't in each specific situation. Keep doing that for many years, and your taste will develop. Remember that you are training your intuition, not developing a set of exact rules.
If I wrote about “how to paint great art” or “how to cook great meals” or “how to build great things” then it would be silly to say “have good taste”—even if that’s part of the answer. It won’t help anyone else to improve in any of those endeavors.