You may be over-estimating how much money I have as a techie, I work in non-profit/academic sector. My retirement funds are relatively paltry compared to what you may assume about techies with so much money (but perhaps still more than US median for my age; googling says median US retirement savings across all working-age households is $95,776), and mostly in managed 401k/403b where I have previously just chosen "lifecycle funds". ¯\_(ツ)_/¯
People make a lot of assumptions about how much wealth random HN commenters or the HN audience in general have, and sometimes I start feeling like I'm really poor compared to all you techie multi-millionaires... but when I actually pay attention to comments, I realize, nope, a lot of HN is more like me (although probably often ashamed to say so).
...yes. Sorry, I don't mean to sound like a jerk, but is this really a question? There are dozens of them: https://www.thebalancemoney.com/the-cheapest-sandp-500-index...
I'm continually astounded by techies who have so much money and so little idea what to do with it. It's not like this stuff is even hard, not compared to keeping up the latest JS nonsense: https://www.bogleheads.org/wiki/Main_Page#mp-gs-h2