I think this sentiment has been around for the past decade+ as geometry has not been a GPU bottleneck/performance issue for a looong time.
Just give yourself enough fidelity to look good enough, and within reason and sensibility. There really isn't a goal/benchmark of what triangle limit to aim for, it just so happens to land around this arbitrary number for many factors. (subject matter has lots of armor pieces, super organic, plus lots of hair cards = inherent high triangle count)
e.g. don't go nuts and author several iterations of subdivisons "just cause", effectively skyrocketing your geo to 400k triangles or whatever.
but also don't skimp out on areas that could use more silhouette/loops/fidelity - we don't need to second guess if we can "afford" it anymore.
so we're working on an indie project using third person and cinematic close-ups in Unity. note, our typific art style allows us fewer polycounts. i was not given a poly target by our engineers but approached just using common sense practices and these are the counts they ended up at. we later created an uprez'd head for cinematics that about doubled its counts from the neck up.
our main character variant A is 11k polies and variant B is 13k. their weapon is 1k and additional accessories are at 1k. the uprez'd cinematic bust is at 5k.
our enemies clock in at around 5-15k.
(for tricount just double these numbers)
our programmer had informed me i could double these counts with no problem. i'm like that old guy that grew up during the depression that uses the same tea bag for 6 months, only it's polycount.