As a tradeable commodity, I'd say that an easy bar for having "made it" would be when you see a BTC exchange-traded fund on a major stock exchange. Progress seems to be happening on that, but we'll see.

As a currency, I'd say that, in the narrow case of BTC itself, failure is baked into its design. The current protocol imposes an estimated upper limit of 3-7 transactions per second on the network. That's just not acceptable for a currency (assuming it has dreams of being more useful and widely accepted than Ithaca Hours, anyway), and the suggested plans around forking are awkward at best.

There are also solutions like the Lightning network. To me, I have a hard time seeing those as efforts to make Bitcoin a currency so much as efforts to create a new currency that is backed by Bitcoin. Sort of like the gold standard of old, where different currencies were backed by commodity reserves.