Shopping for a new mattress, and landed on the Zinus brand. Thousands of great reviews, but the bad reviews speak to asthma and fiberglass.
This is from their FAQ:

If Zinus is transitioning away from fiberglass, what’s your new plan to meet flammability standards?

Given our steadfast commitment to customer satisfaction, we are constantly looking for ways to create mattresses that reflect evolving consumer preferences and technologies. As such, we are transitioning away from using fiberglass to a rayon-based fire safety barrier in all of our mattresses.

I chatted with Zinus to see which mattresses have "transitioned" from fiberglass and they responded with this:

...we do not use fiberglass on our mattresses. Fiberglass is micro-sphere shaped and is staple, so using that would definitely poke out holes on both the cover and the foam. We use fire barrier which are filaments woven onto the foam. Fire barrier are no threat to your health.

Does anyone have any intel on mattresses and fiberglass? Any mattress recommendations? Comfort level with Zinus is sinking...
Thanks!