> A house has a more important primary purpose
Aren't houses purchased for the intent of renting them out investments? This would argue that they are not. Seems to be proving too much.
Despite the title, this section of the article is actually about how illiquid houses are. Which, again, proves too much - old bonds are also extremely illiquid, but no one says they aren't investments.
> A house can’t be an investment if you never plan to sell it
I buy plenty of VFINX that I don't intend to ever sell. I buy them for the dividends (incidentally, the same reason I would buy a house).
> Thinking of your house as an investment can lead to equity stripping
This says that thinking of your house as an investment leads to poor decisions, not that it is wrong. Sure, maybe it does, but that's a completely different argument.
> The carrying costs of a house are too high for it to be an investment
The carrying costs of a house are typically negative, unless you conveniently forget that a house covers a short position and is thus paying you back (in the form of covering your rent). Which the article does.
> Your house won’t generate cash flow
Again, it is covering a short position. It saves you from paying rent, which is mathematically identical to forcing you to continue paying rent but paying you the same amount.
> Price appreciation is the magic ingredient, but it’s not guaranteed
This is true of all investments.