The unregistering of already registered classes is expected behavior,
however this was done silently and can be unsafe as two Addons may have
the same names for operators and in case of name collision the addon
registered first will break silently / start behave unexpectedly.
So reporting the unregister step seems reasonable.
During Addon development, this might seem noisy when classes are
frequently updated, however catching the problematic cases instead of
being silent might be beneficial.
Part of #116370
Philipp Oeser