I am also confused by this statement. The most generous interpretation I have is that this number is quite high, and therefore, the bar to being more 'affordable' than this is 'low' in that selling, say, a $500,000 ADU appears quite affordable in comparison. I don't know though, it obviously all seems quite absurd. The other interpretation might be that SFH are far more than this, but one would think you would include the average price of SFH when making such a point.