> There was a popular internet sentiment ~10 years ago where everyone was convinced renting was superior to buying. "Invest the extra cash in an index fund!"
I think you're stating the sentiment wrong, as someone who did and still does to some extent sympathize with it. The default view in American personal financial discourse has been that you need to buy a house. The heterodox view to which you're referring was that renting and investing is not obviously worse than buying a house. I don't recall any widespread view that you would come out way ahead by renting.
And, to be fair to that viewpoint, compared to buying a house outright, you would have been better off keeping your money in the market and renting over the last five years! S&P is up 91% over that period, and that's not even the total return index! Housing is up quite a bit, but in most places it is not up 91%. I sold a house in the Bay Area around five years ago for around $2.4M, and Zillow is telling me that it's now worth a little over $3M. Zillow could be off by a few hundred thousand in any direction, but I doubt it's off by $1.5M.
What the viewpoint fails to consider is the availability of extremely cheap leverage for houses. If housing does go up, and you have a 4:1 debt to equity ratio, then your appreciation is 4x the asset appreciation if you're at the beginning of your mortgage. If you're the person who bought my house, your $700k of appreciation on a downpayment of $500k is a 140% return (before transaction costs). Of course, if housing ever goes down . . . well, we all remember that well enough.
All in all, I'm not sure the case is closed on the rent and invest vs buy issue. Things look very favorable for buy over the last five to ten years! There is no question about that. However, I personally am not sure how to adjust for the risk associated with the increased leverage you use when you buy. I don't think it's an apples to apples comparison.