I think scaling is not a big problem, the efficiency of the blocks will get improved by innovations like segregated witness and things like the lightning network will bring a part of the transactions off the blockchain. More of these innovations will pop up in the coming years. In worse case the network can get overloaded for a while and this will cause a small raise in the transaction costs. The biggest opportunity at the moment for Bitcoin to get a huge market cap. that will cause a big price advance is adoption as a store of value and as reserve currency. These use cases will not bring much extra pressure to the blockchain, because they don't require many transactions.

I think this guy is totally right: