I'm thinking of those iconic scenes where a person runs from the T-Rex (or OtherBigDino in JW).
- This is a predator that probably can't push over an entire large tree that easily (we never see one doing so).
- It has no reacharound-capable front limbs.
- It has a skull whose size makes it awkward to reach around a tree-trunk and down maneuverably (with cars it had to push them out of the way, not reach around the sides), and whose angle of attack if tried would make it much easier to avoid the jaws. By which I mean that it's easy to bite a moving target if you can respond to its movements "in the open", but if it's got to lunge downward and around an obstruction, the positions it can quickly shift to, are much more limited and it's less easy to quickly change direction. Also the area of danger is smaller (a bit like avoiding any object from above vs one that can sweep across the landscape).
- It's portrayed as relatively agile for its size but not likely to be able to take the kind of quickly changing direction of small steps needed to run around a tree to attack free of obstruction.
- Whenever it's shown attacking a person behind some object, it's either an object with limited height that can be reached over (car, fishtank), or pushed aside/flipped over/moved.
TL;DR wouldn't ducking behind a large tree have been far more effective in the JP universe, as portrayed?