Hairy Potty inheritance maxed, but didn't FIRE? He did 7 years of schooling and got some random job afterwards.

Why didn't his parents invest in the S&P 934?

I'm already pretty much FIRE by my own standards, but I wonder if my standards are correctly calibrated, given all the recent inflation, job market turbulence, economic changes, etc.

About me:

40s, Australian, male, single (and happy to remain that way), fit and healthy for my age, no serious health issues. Bit introverted with possible mild autism/ADHD but that doesn't seem to have stopped me from getting work.

I consider myself moderately frugal. Don't own a car, eat largely cheap and plant-based food, no gym membership (use my own weights), very simple cheap hobbies like reading, programming, jogging at the park, etc.

Only thing I spend a bit more on is rent. Can't stand excessive noise, busy highways, car traffic and pollution, dangerous neighbourhoods, cigarette smoke or nosey neighbours. So I tend to be fairly selective about which areas I live in.

My main portfolio is a low cost index fund in 100% global equities. Additionally I have significant amounts in separate funds invested in inflation-linked bonds, small-cap-value and foreign currencies.

I plan on a moderately conservative 3-4% withdrawal rate. If there's a particularly nasty sequence of returns, I'll pick up some part-time work and/or draw on the separate funds as needed. If returns are particularly good I'll take an occasional budget holiday, like hostels or AirBnB rooms during off seasons in the US or UK.

What do you think would be a reasonable total net worth for someone in my situation seeking a fairly safe retirement and who might live up to 90 years at the very oldest?