Those rocks - particularly near Snow Stretch, have always been that way. Trees on Toulan are hit or miss (bad pun) but I've noticed vapor trees in a variety of locations. The Jelly Swamp also has many such "plants". I have always disliked this - it is a spell-breaker. I don't notice the trees too much because I've played as if they are solid since the days when 99% of trees on the old Calypso were non-collision objects. The rocks are more noticeable because targeting and shooting through them so obvious while hunting.
It might not be the most important thing, but it would be really cool if big rocks and trees were all solid.
Peace, Miles