On the definition of "hit" in the context of "hitless"—especially regarding Owl's shoulder bump.

So I know this will seem like incredibly nitpicky semantics to a lot of people (and you'll be right), but for us weirdos who still think about these things I would be interested in hearing your takes. (Please note that it's common to distinguish between "hitless" and "damageless." As it's typically construed, something can be a hit even if it does no damage, and this post is about hits in particular.)

I'm reading Team Hitless' rules for Sekiro and they says that "A Hit is defined by a loss of health and/or stagger caused by an enemy." Seems clear and concise. But they later say "Blocking an enemy counts as a hit, but a deflect does not." This might be written with Kuro's charm in mind, but as it stands it does not perfectly cohere with the previous definition of "hit." What if you block ("imperfectly parry") an attack that neither does vitality damage nor staggers you? By the first quote this is not a hit, but by the second quote it is a hit—so this is where things gets a little tricky.

As an example I've been digging into Owl (Father)'s elbow/shoulder bump in the firecracker combo by comparing what happens when you deflect, block, and just eat that attack. And as far as I can tell, regardless of how/whether you defend against it, it sends you backwards a bit and has literally no other effect in any of the cases.
It never does vitality damage and the image below is of my posture bar immediately before and after eating the push, so you can see that it does no perceivable posture damage either (this regardless of whether you deflect it, block it, or just tank it).

Posture meter immediately before (above) and after (below) taking Owl's shoulder bump.

However, as far as I can tell, just taking the push when your posture bar is completely full will still break your posture and cause you to stagger. It's a bit tricky to test this so I'm not 100% sure if it also staggers you if you block it with a full posture bar, but my guess is that it does.

So sticking closely to Team Hitless' definition above, even tanking this attack (or indeed Owl's stomp, which does massive posture damage) should only count as a hit if it breaks your posture/staggers you. But I suspect that they indeed count this bump (as well as the stomp) as a hit if you just stand there and take it to the face. Indeed, by the second quote above, these would count as hits even if you block them.

I'm sure we can all agree that it's not a hit if you deflect it, but what would you say about the other two cases?
Would you count it as a hit if you just tank it without staggering? Would you count it as a hit if you block it without staggering?
One way of trying to answer a question like this would be to ask "What does it take to completely/properly defend against this attack?," and then conclude that it's a hit if no such defenses are successfully employed. The problem with this is that, unless your posture bar is full, the attack has exactly the same consequence whether you defend against it or not, so it seems hard to distinguish between a failed and a successful defense against it. From Owl's perspective, the bump is successful even if you deflect, because it has the same effect anyway: It pushes you back a bit.

Do you think it is possible to formulate a reasonable definition of "hit" in Sekiro by which it counts as a hit if you block this push without staggering? I'm not sure what to think myself, because on the one hand it seems kinda "imperfect" to block it, but I also struggle to come up with any such definition that doesn't just include it entirely ad hoc.

What do you think?