[Groxx]

>is it viable to use for end users?

For mining, no. This was always seen as the future state, it was just a question of when. Not too long before the first ASICs started coming out, it was already basically not profitable for most people, you had to be running a limited set of GPUs and be in a place that had cheap electricity to make any real money.

>Is it just that everyone uses fractions of BTCs now?

Since they're roughly $100 each, yes, basically everyone uses fractions. Thankfully they're way more divisible than e.g. pennies, and if the value / userbase goes up by a couple orders of magnitude, they can be made more divisible, also unlike pennies.