When creating multiple Pipe Tool objects (either by duplicating them from the menu or creating new ones), their names in the Outliner reset to the default dash_pipe. This happens after saving or after modifying the curve - basically, any manipulation causes the name to reset to the default. At the same time, the labels inside the Dash tools are preserved.
Because of this, it’s almost impossible to manage a large number of pipes, as you constantly have to click through and search for the correct one.
Additionally, after rendering to EXR, Cryptomatte treats all pipes as a single object. I tested this with different ID types, but the result is the same.