First off there is no black and white definition of 'mass acceptance', how will anyone even know when we have/have not achieved 'mass acceptance'? On the assumption that somehow everyone is in agreement as to what defines mass acceptance, I'd say we attain some degree of stability with the possibility of climbing higher on the basis of hope for greater acceptance and merchant/consumer integration.
That's true but there are certainly plenty of metrics that could be used to assess the level of acceptance. I don't think anyone would argue that at the moment we are far from 'mass acceptance' because you still can only use BTC (or cryptos in general) at a small handful of places and the majority of transactions are still just occurring between miners and investors (and between investors and other investors.)
I think any "mass acceptance" would require that cryptos be used more as a currency than a get-rich-quick investment. I also think we'd need to see some amount of people getting paid in crypto before I would personally consider it to have reached 'mass acceptance.'
Another huge one is the fees. Eventually cryptos are supposed to support the costs of continuing to secure the network by generating tons of small transaction fees. So it seems that there also must be enough transactions going through in every block to make it worthwhile for a certain level of hashing to continue solely for the sake of earning those transaction fees, in order to say we have reached 'mass acceptance.'
