Is this wall load bearing?
The only thing bearing on that wall are shampoo bottles.
Knock away.  The wall is empty.  Note that the end of the porcelain tub is open,
so something will have to go back to cover it up.  When it's open you can inspect under the tub for horrors.

But you'll also want to remove the wall sheathing all around that tub, and read up about flashing and backer board.