If everyone whinging online signed up to a party today, started attending every single local meeting from tomorrow onwards, put themselves forward for roles within that party, actually put in time and effort to get selected, get elected, move up, keep moving up, keep aiming higher, we’d have a completely overhauled political system in 5 years.

yes, if the system was built for people this would work. Currently it's built for people with money and incumbency. The new guy in the race is going to need one hell of a financial backing to get his name out there. Do you think they just mail shit to people for free?