It is still reasonable general audience advice. In one interview, I heard fluffypony add something to effect of "If you are an extreme speculator then sure go ahead and speculate". For anyone else, the advice is perfectly okay. This is not a proven asset, it isn't in a proven asset class. There can be bugs that completely destroy the currency.

As for "extreme speculators", I question how many people really are that. Extreme speculator to me, means that you know that your investment has a significant chance to lose all or most of its value and accept that when buying in. That takes significant financial and emotional preparation and resources. How many people here on the speculation thread raise a stink and declare XMR dead every time the price drops by 20-30% (still 70-80% less of a drop than the the full-loss scenario)? What happens when we see a 90% drop, as has happened to XMR before, and to BTC multiple times?

How about, "If you are going to be upset when your investment loses 20-30% of its value (not to mention 90% or more), then don't buy Monero"? In practice that's going to be the same thing for most of the audience.