Once more a true classic in every sense of the word. The thread has a decade, the topic several centuries.

A "false contralto" is fairly easy to describe: a person who can sing soprano parts, or could, or would be able if properly trained, but actually sings contralto parts. Female voices differ from male ones by the fact that their lower limit is almost uniform. Most sopranists can sing below the trable clef easily, in particular when they are out of health, e.g. by smoking. But the sound makes the difference.

Many prominent sopranists tried themselves in alto or low mezzo roles later in their career, when they could no longer sing high notes; the most famous one was Maria Callas.

Genuine contraltos are not rare, but in the minority, somewhat mirroring the statistical relation between tenors and bass-bariton-type voices. In both cases the criterion seems to be relatively clear-cut, whereas there is no such clear line between basses and baritones, or between sopranos and mezzos etc.

Anyway, music critics (of whatever qualification) are usually paid for impressing their readers, rather than informing them.