Stock price when the opinion was issued
For a long-term investment, iShares Core S&P US Total Market (XUU-T) or iShares S&P 500 Index (XUS-T)? This has largely been a large cap recovery. He also likes the mid-caps. As the US recovery continues, that benefit is going to spread to the smaller caps. Right now he likes the US version. Just coming out of their recovery, he would be more going into the large caps as he has done in the past. However, he is fine with these.
This drills down past large caps into micro caps, small caps, etc. If you want to be in this market, this is fine, but he is holding back from them because it is still a “large cap market” as far as he is concerned.