Align an object relative to ifself is not possible, so let's create 2 use cases.
Summary:
The issue is with the "Object/Align and Distribute" (Shift-Ctlr-A) tool. It's more of an incomplete feature (feature request) than an issue.
If you have only one object selected, it does not make sens to Align relative to the "Last selected", but it does make sens to align it relative to "Page" or the "Drawing". Same for "First selected", "Biggest object", "Smallest object" and "Selected area".
So (in my head) there's 2 use cases, if I want to align relative to "Page", I select only one item as I rarely (never) align multiple objects to page. If I select multiple objects, it's to align relative to "The last selected", but Inkscape does not make a difference between the 2 and save te last choice, it's annoying.
I realize that when I want to align multiple object "Relative to" "Page", I want to align them as a group relative to page, so they stay at the same relative position. I then need to group them, align "Relative to" "Page", then ungroup them.
What I would like to happen?
Remember my last choice for aligning one object differently than aligning multiple objects.
So that the default "Relative to" change if I have 1 or multiple objects selected.
Plus, if I have multiple object selected and align them "Relative to" "Page", the group of selected objects should be aligned "Relative to" "Page", not the individual objects.
So basically handling the whole selection as one object if "Relative to" "Page" or "Drawing". Or handling as a group of object if "Relative to" one of: "Last selected", "First selected", "Biggest object", "Smallest object" or "Selected area". ... Not sure about selected area as I never used it...
The following are not really useful
Steps to reproduce:
Select one object and click on Object/Align and Distribute/Relative to:
What happened?
Try to understand how you can align one object relative to itself.
What should have happened?
The Option to align relative to itself should not be present.
Version info
Inkscape 1.3.2 (1:1.3.2+202311252150+091e20ef0f)