Magnolia question

This is something I've been wondering for years now and I want to write it down somewhere so I can remember to come back to it - How do magnolias, especially their annual dump of magnolia leaves, interact with native California gardens? The magnolia in question is native to the Southern states of North America. 

The leaves are thick, PLENTIFUL, and slow to break down. For a long time I've been wondering if they'll make a proper mulch.

Reasons I want to leave them:

- I like having leaves around

- It's a good habitat for bugs

- Having free mulch would be nice

Reasons I am compelled to rake them up:

- Magnolias are allelopathic (contain compounds that inhibit the growth of other plants)

- Because of their size and the time they take to break down, I am worried they will smother some lower smaller plants

- Social pressures

So what I am really wondering is if the allelopathic qualities are significant enough that they negate the benefits of using the leaves as mulch. And if native plants are particularly susceptible or resistant? Google does not answer this, obviously. There are some articles on why they make good mulch and why they don't but they're all from a very broad non-region-specific view, just kind of like Leaf Facts. IDK I'll check Dave's Garden. And maybe do an experiment.