Checked the SVG code. The code of the path still contains the skew transformation matrix after the clipping path is removed. Deleting the transformation matrix line removes the skew effect, it doesn't transform the result to the same as the skewing was applied to an unclipped path. That can be considered as a bug. It can be also a decided property. Only Inkscape developer team knows.
If one applies skew to a group the group also gets the same removable transformation matrix, but the matrix vanishes if ungroup is applied. That suggests it's a bug.
SVG code can be seen and edited in a text editor. As well one can use in Inkscape Edit > XML editor dialog to see it and fix it:
The red curve is an open path which was put under a clipping path, the image was skewed and the clipping path was removed by applying Object > Clip > release.
Deleting the transformation matrix line returns the original path form:
Applying the skew transformation to the unclipped path doesn't insert transformation matrix line, but edits the path nodes and handles destructively. The transformation matrix in the code affects also how the path is rendered.
Here's the code for a skewed group of 2 identical open paths. I must admit that it's annoying for a person who expects uniformly wide paths. But as a compensation he gets a removable effect:
I use Inkscape v1.1