Well that is the goal and purpose of cryptocurrencies in general.
But, do you really think bitcoin is ready for that? We already know it's limits and weaknesses. The moment the network clogs, transaction fees skyrocket and speed gets really slow. Add that to a very volatile nature, it's no surprise that users and markets find it hard to use it as a payment system. We know these numbers, and guess what, that's nowhere near the numbers we'll reach if people use it, say, in amazon or even smaller online markets.
The development is just extremely slow. I do like to see cryptocurrencies do what it's meant to do, but I guess we'll still have to wait a couple more years for that.
I disagree with your point of view. You seem to be putting the cart before the horse. Bitcoin is not the only currency which can be used for making payments. If we take litecoin as an example, a coin which is technically just a more advanced version of bitcoin itself, there are no such issues as high transaction fees or slow confirmation times (and it has LN activated for over a year by now). But it is still not used widely. What does it tell us? Basically, that there is no demand for crypto as a means of payment, and this is the real problem.
Also, volatility is not an issue either as there are plenty of ways to make it irrelevant, which is what payment processors and gateways do on a daily basis.
I don't see why volatility is not an issue(though I'm open on being educated), I'm sure you know the pizza story. Even the day to day changes can be scary for a businessman.
In my opinion, for a cryptocurrency to be accepted widely as payment system, it needs to actually compete with existing payment systems, like paypal or visa. Transaction speed of most cryptocurrencies are nowhere near these payment systems. The fastest we have is ripple, but it has such a bad name I doubt people would use it.
Also, the low demand for cryptocurrencies as a payment system is not the problem, it's the effect of these problems.