I'm 1,120 SC short of LTG. I first flew Qantas in 2009. I flew once a year between 2011 and 2015 (mostly leisure) then with a change in role, I began flying internationally (all Y class) for work and achieved lifetime silver Jan 2020. Covid hit and I didn't fly for three and a half years, so I made no progress at all towards LTG. I've had to use DSC offers to strategically reach Platinum status most years as my business travel is all Y class. Based on projected travel, I should hit LTG around 18 months from now.
As has been discussed by others, there's little incentive to keep flying Qantas after achieving LTG, given LTP is not realistically achievable. LTG will come in handy when I start travelling domestically with my wife and children when they (children not my wife!) are old enough to appreciate travelling around this beautiful country.
I saw someone posted earlier that they achieved LTG just six years after joining Qantas which is impressive going! It would be interesting to see how quickly others have moved up through the tiers. For me, it took 11 years from joining Qantas to reaching LTS, then if you ignore the three and a half years forced grounding, I resumed travel mid-2023 and I'm on track to reach LTG by the end of 2026.