I think the evidence shows that massive bodies bend light, magnetism physically cannot.
To address magnetism: photons are EM emissions, and only influenced by matter, rather than the EM field itself; this surely rules out magnetism as a bending factor. Photons, directly, are unaffected by magnetism. The electric force is matter-based, photons are just massless force carriers manifested by the electric force, only reacting through matter, not the field itself.
To address dust, nebular gas, or the like: matter and it’s force carriers can scatter light, which wouldn’t give distortion, just absorption and emission of new photons. So, dust’s mass can redirect light via space-time curvature or re-emit it via direct interaction with the electrons*. Spectral analysis can show this through matter-wavelength signatures (*to emphasize the latter: atoms will accept and re-radiate photons per their electron structure/orbit as it’s influenced by absorbed photons)
The deeper point is: light is reflected, refracted, and diffracted by interaction with matter. Gravitational lensing is redirection of photons, not by matter itself, but it’s distal action on space-time. This is observed clearly in astronomic endeavors. The most profound observations show a halo-like curve of incoming light (of a Doppler signature that is obviously sourced behind the the object). This means it’s not re-emitted by this body, but bent by it’s massive existence.
I hope a real astronomer can give an example. Otherwise, upon viewing apparent massive bodies which are specific to this phenomenon, we can see photon-curvature as well as re-emmitance. Spatial dust and other matter has a specific sign. Some light really is lensed, not re-shone. We assume the lensing is space-time curvature via mass, as there is no better explanation within the Eisteinian-Physics and QFT paradigms.
To reiterate: magnetic bodies just don’t seem to influence photons via their field, regardless of their field strength.
The Broad Spectrum Life 
Absolutely true scientific thoughts,dear!!
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It is good you answered this question. I certainly could not.
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It took me a bit to figure it out. Like Kennedy said, “We do not do these things because they are easy; we do them because they are hard.”
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Sometimes the way stuff should work and how it actually works do not match. This idea fascinated me. There is so much we do not know, so much yet unknown. To the explorers! 🙂
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Indeed. This explained only enough to make more questions. It’s hardly an answer.
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Indeed! Never stop asking how, why, when, who, where, what? That’s where all the new discoveries happen. Thinking all there is to be known already is, that’s where most exist. Realizing there’s so much we don’t know, so much more to discover, and exploring that bleeding edge, that’s the good stuff! 🙂
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I highly approve of that comment. Keep learning what you don’t know, such that you know you have more to know.
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