Well the peso is usable for cash transactions. The unbanked only lack the ability to transact online. That is where the action is in terms of marketing to them.
I presume you mean M-pesa?
https://en.wikipedia.org/wiki/M-PesaStill, this does not represent a good store of value, and crypto in general probably isn't that because of the massive volatility. This is why things like nuBits and bitUSD are compelling offerings if they could be made to work more robustly.
No I meant the Philippines peso (the national currency). Aren't you aware I am living in the Philippines.
I don't think stable store-of-value is the issue. Investors don't want it, and my intuition is hypothetical microtransaction spenders don't care much about it (because the value at risk is so small) and are much more interested in what the hell can they do with this silly online currency that they can't also do with fiat.
Edit: one could argue that pegged assets would be functionally equivalent to a digital credit card, being denominated in the user's national currency, thus making the unbanked instantly banked in their national currency. But the problem is there are losses involved in any peg and businesses already operate on low profit margins due to competition. Also there is no opportunity to do clever marketing based on rising value, as the currency can only be funded by real value equivalent to the pegged asset value.