Hi,
I have confirmed this.
If we click the Remove Icon under the details screen of the list, then the list item would be removed, and can't be restored from the recycle bin.
The formula used under the remove icon is:
Remove('Testing list', BrowseGallery1.Selected); If (IsEmpty(Errors('Testing list', BrowseGallery1.Selected)), Back())
The explanation from the PowerApp formula reference article for this function is:
Remove – Removes one or more specific records from a data source.
Currently I can't find any function available in the formula list which would obey the deleting rules defined in SharePoint.
I will report this from my side, hope there would be update on this part soon.
Regards