We can accurately predict lensing well enough to see the impact on particles of light - over billions of miles. We can't explain it.

The universe is still full of many mysteries. If we knew the why, we'd stop doing science. Our understanding is incomplete and that's okay. It gives our species something to strive for.

Do you really understand particle physics well enough to truly understand how your cell phone works? We can predict, model, and observe. We can get results. We don't necessarily know or why the results are the way they are.

Edited to add: I find it interesting enough to sometimes point out that we used electricity before we even knew about electrons. Being able to do something doesn't mean understanding.

We used simple machines, long before we understood them.