Do you actually believe the “future returns will be lower” narrative?

Everyone always says the U.S. stock market averages \~10% long term (thinking S&P 500). But now it feels like every “expert” (capital market forecasters) is suddenly calling for 4–6% returns going forward because of valuations, interest rates, etc. At the same time, people in the past didn’t exactly predict the massive returns we’ve already had. So what’s your take: Do you actually buy the idea that returns will be significantly lower going forward? Or is this just the usual “this time is different” narrative in reverse? If you had to pick a number for the next 30–50 years, what are you betting on? Feels like people have been predicting lower returns forever… and the market just keeps doing its thing. Curious where everyone here lands.