Thanks for linking the video, actually made me feel very nostalgic about both (series of) films!
The Bakshi film is ridiculous at times, but some of the visuals are very powerful.
I would ask though, how do you draw the line between plagiarism, deliberate homage/ intertextual reference, and simply something leaving such an impression on your imagination that you (possibly subconsciously) echo it in your own work?
Personally, I don't hold most of the parallels against Jackson&co (especially as some of these were a bit of a reach - there's a limited way of sensible options how to show say
Gandalf arriving on a cart to Bag End), but a few are a bit jarringly similar, such as the hiding from the Black Rider under the roots of the tree. The Bakshi version manages to be much creepier, too!