Well I thought this was normal behavior of a CAD drawing as I always did it this way in AutoCAD, ProgeCAD and Draft Sight.
Other thing is that I don’t see any logica in making several same blocks to have mirrored or rotated versions of 1. Like a normal door for example. But thank you anyway for the quick reply. I’ll keep the 3.23 version to be sure this works in a way I like it
I’m unable to mirror a block without mirroring its text in either Autocad or Draftsight. You’d have to use an attribute to achieve that (you can also do that in QCAD).
See:
https://forums.autodesk.com/t5/autocad-forum/prevent-text-mirroring-in-a-block/td-p/7167253
Left unanswered …
Being the advocat of correct non-uniform scaling I am very pleased with that.
A transformation matrix is all the proper math at once instead of all the
‘If’s, IfNOT’s, scale x, scale y, exclude this or that’ in the transformation scripts.
IMHO: if I say ‘mirror’ then I want the mirrored image.
For 2D: The 1:1 reflection like when you would hold a printout in a parallel plane before a plain mirror.
For 3D: I can hold my printout in a none parallel plane. Or the mirror is.
Morphing: I can use more then one mirror, not limited to a plain mirror.
So mirror it!
The same questions can be asked for Block angles.
Q: would I prefer to read upside down with a 180° rotation? Or would I like it ‘readable’ 
Rotated should be the answer but it looks odd.
And what with the angle of dimension texts?
Readable off course.
So it all boil down to preferences …
Some of them are preset by the ‘common’ art.
Common can also be a ‘bad habit’ or ‘outdated’ or ‘compatible’.
Still looking for a way to mirror text in Y to create my mirrored Block clone … 
Regards,
CVH
Ok you are right. If it’s an attribute it’s possible. A block such as a door is block & attribute text.
Since then I was wondering how to mirror text …
CVH: From 3.24.3.9, you can mirror simple texts if preference Edit > Drawing Preferences > General > Text > Mirror simple text is checked.