Split wood and deformed joist hangers. Please help identify if there is a problem

Hello

I'm planning on remodeling the stairwell and wanted to convert the 80s walls to railings. I started taking out all the drywall until I reached the very top resting area where there is an overhang closet. I'm planning on removing the closet and putting up horizontal railings there as well. Behind the the closet's bottom drywall I noticed 3 sections of horizontal studs under the floorboard that are split and and it seems they were supported by metal hangers but even the hangers deformed. You can see even the hanger on the right side it is completely deformed/ almost flat. Not sure what that one was even supporting ?

The other question I want to remove the closet studs so I can put up the railing but not sure if they really support the ceiling above it. Is it safe to remove them ?

Please refer to drive link for pictures

https://drive.google.com/drive/folders/105jV3Hx1tlOqL-HCGWnJopbChH4o3JcB?usp=drive_link