Version 7.5.3 is really considered newer than 7.5.3~deb10u1 (beware, it
is a tilde, not a dash):
# ge = "greater or equal"
$ dpkg --compare-versions 7.5.3 ge "7.5.3~deb10u1"; echo $?
0 # means "true"
Indeed, according to the Debian Policy [1]:
[1] https://www.debian.org/doc/debian-policy/ch-controlfields.html#version
The lexical comparison is a comparison of ASCII values modified so
that all the letters sort earlier than all the non-letters and so that
a tilde sorts before anything, even the end of a part. For example,
the following parts are in sorted order from earliest to latest: ‘~~’,
‘~~a’, ‘~’, the empty part, ‘a’.
Therefore I guess this bugreport can be closed as invalid, but I prefer
to let others decide.