How will that statement Invest what you can afford to loss be scaring to newbies? That's just the reality of bitcoin investment you will definitely be gambling with your investment the moment you are using the money you can't afford to loss because there will be a point where you will be willing to sell out your bitcoin in a very short time because you were investing with the amount you can't do away with.
Bitcoin investment should be done with our discretionary income, your leftover income after you have sort all necessary expenses such as family needs feeding, children school fees and so then you an use the remaining for your bitcoin investment which is your discretionary income. So investing with what you can afford to loss shouldn't be a scaring statement to newbies that is what they need to know.
The difference is that you are not investing what you can loose but what you can hold. There's a clear difference!! What you can loose makes it a gambling which is Trading. Whereas investing to hold means Bitcoin Investment. Investing with discretionary income particularly by DCA means you are aiming long term holding. Discretionary income doesn't mean anyone would love to loose the money. Bitcoin Trading is the reason behind that statement "Invest what you can loose"! Don't confuse the two. I don't know it all but I still know that anyone that really understands bitcoin and won't ask anyone to invest what he can afford to loose but what he can afford to hold for long.
Somehow I don't like the word you can afford to lose especially if we are dealing about Bitcoin since somehow we are not losing especially if we are accumulating intended for long term.
Those losing situation will only occur especially if you are trading and you decide to sell your Bitcoin because you are afraid to lose more. In that situation I guess its good to use the word invest only what you can afford.
But somehow people have different takes towards this discussion and what's important is we know what to do and aim to buy then HODL Bitcoin for long term.