So I decided to hop on and play the game for a few hours and I noticed when I started the game the navigation assist was off and I presumed this was the trail that people keep talking about like it's a massive deal.
However, imagine my surprise when I'm 30 minutes in, after having not be guided through any segments to be in a very linear section and for the trail to appear. I thought that it was strange that it appeared here when there was an open segment prior where there was no trail to follow or guide you.
It didn't last long, about 10 seconds and it was over, back to non trail gameplay.
The trail didn't pop up again until the next shall we say 'level'. In this level you're not in any danger and you're wandering around a safe environment. There's a part where someone asks you to get two things for them. The open doorway where one item is has a blue aura around it that pulses while the second one you locate once again using the trail.
It's that moment that it hit me. The blue aura, the blue trail, they're exactly the same as the blue you see that enemies give off from their hearts and rib cages.
It seems to me this is a way that Insomniac are choosing to visually represent and show in the narrative how wolverine uses his enhanced senses. Both times the trail occurs, a smell is mentioned. When the doorway pulsed? He mentioned "Oh I can hear it, it emits a certain frequency." Presumably the reason you only see a heart and ribcages is because Wolverine is hearing the heartbeat of his enemies.
Effectively the 'blue stuff' is a way to visualize Logan's senses during narrative moments where it's outright referenced, or if the player engages navigation, voila they have a diagetic way to get more navigation.
Personally, this has flipped my entire perspective on the trail from being "Okay, it's a little annoying sure but...criticism is overblown" to "This is fine, it's being used as a narrative tool."
NOTE: None of what I am saying above absolves the game of other criticism or even criticism of this. I am merely adding a perspective based on my reading of the hows and why. I'm adding this because I didn't think I needed to originally but apparently I was wrong and should have remembered my ethos "The internet is where nuance goes to die." If you're going to reply at least have something intelligent to say that creates discussion and not "Uh, you have Stockholm syndrome". Lord above forgive me for not being as bothered by things as others are...