Some will argue that 1500hrs of light aircraft flying gives you "command experience and decision making abilities", which is invalid because flying a light aircraft isn't like flying an airliner, you're going to be waiting as an FO for a considerable amount of time and picking up your command judgement that way anyway, and there's been hundreds if not thousands of airline captains in Australia who didn't have that "required command experience" when they joined an airline and they're doing just fine.
Disagree. If you are flying charter/RPT that will give some exposure to exactly the same decision making that you will make as an airline pilot. Yes you are right that it is not the same however it is similar and the decisions are the same just less complicated.
Also if you are an FO your arse is not on the line. THAT fact alone changes everything. No one is there to save you when you are PIC regardless of the size of your machine. The theory I assume for the cadets is they hire well above average ability and give them allot of time to get up to speed. This doesn't help the PIC if the cadet is in the RHS and something serious happens early on.
Funnily enough the original QF cadetships 50+ years ago sent their protégés off to GA to start with.