CLN: remove unreachable, unnecessary axis kwd (#53991)

Author: jbrockmendel

pandas/core/generic.py

@@ -8052,10 +8052,8 @@ def interpolate(
             )
         else:
             index = missing.get_interp_index(method, obj.index)
-            axis = self._info_axis_number
             new_data = obj._mgr.interpolate(
                 method=method,
-                axis=axis,
                 index=index,
                 limit=limit,
                 limit_direction=limit_direction,

pandas/core/internals/blocks.py

@@ -1396,7 +1396,6 @@ def interpolate(
         self,
         *,
         method: InterpolateOptions,
-        axis: AxisInt,
         index: Index,
         inplace: bool = False,
         limit: int | None = None,
@@ -1427,27 +1426,12 @@ def interpolate(
                 return [self.copy(deep=False)]
             return [self] if inplace else [self.copy()]
 
-        if self.is_object and self.ndim == 2 and self.shape[0] != 1 and axis == 0:
-            # split improves performance in ndarray.copy()
-            return self.split_and_operate(
-                type(self).interpolate,
-                method=method,
-                axis=axis,
-                index=index,
-                inplace=inplace,
-                limit=limit,
-                limit_direction=limit_direction,
-                limit_area=limit_area,
-                downcast=downcast,
-                **kwargs,
-            )
-
         copy, refs = self._get_refs_and_copy(using_cow, inplace)
 
         # Dispatch to the EA method.
         new_values = self.array_values.interpolate(
             method=method,
-            axis=axis,
+            axis=self.ndim - 1,
             index=index,
             limit=limit,
             limit_direction=limit_direction,