This plant is tiny. Has succulent leaves. Gets eaten a lot probably by mammals rather than invertebrates.
Closest I can get is a Calandrinia but no idea really.
I have resumed testing one or two plant ID apps and this suggestion came up for a plant growing near me. (Another app came up with a heap of suggestions that may not be present in Australia.)
It may of course be a blow in ... from somewhere else including other countries. We haven't seen it here before but it is pretty small and seems to be chewed by the wallabies so we may have missed it in the past. If it is totally foreign it will get removed.