Bent frame

If that's all that got damaged then yes the frame rails can be repaired. I'm sure a shop can do better than what the manuf boogered together. Just inspect the box where it attaches to the frame and make sure none of the wood (or aluminum if that how it's framed) was damaged!

WOW...if the frame is bent down 6" then you will have trailer structure damage like in the sidewalls and back wall pulled loose from the floor or floor pulled loose from the frame. If it didn't then look close at the roof and top of the sidewalls above the bent area.
I would have someone with this type of experience check it all out for you.

A experienced big rig trailer repair shop can repair the main frame rails/cross members....stronger than OEM.

What does your insurance company saying ??

As IDman asked, when the tree fell it caught the spare tire, which caused the bumper to bend, which then caused the frame to bend. It also demolished two bicycles. I am not good at posting pictures, but the impact caused the frame to drop about 6 inches back to nothing at 4-5 feet from the bumper. Can see wiring, pipes and the "black" tank in the gap, so I am concerned about the integrity of the water system and electrical. Also concerned about the long term endurance of the body and frame as the damage is at the end of the trailer where there would be more bounce as you travel down the road. For the sake of 6 inches, it did no damage to the "box" but in sure did bend the frame. Lost five trees in the storm that included up to 80 mph straight line winds. The trees were pines that had been planted in the 30's by the CCC. Pines are pretty weak.

As flimsy as the frames are it wouldn’t take much to put it back stronger.

A good welder can fix anything except a broken heart ,

My opinion would depend on what the experience and skill of the shop is. Some I would trust, some I wouldn't let them check the air in a flat tire.

I think my insurance company would write that off.

I’d trust a frame shop to fix it.

Curious as to how a falling tree could damage the frame (which is on the bottom) and not damage the more fragile "box" of the trailer. Could you please show photos or explain?