You don't understand, the Bitcoin protocol isn't designed for massive amount of transactions, because all transaction has to be stored, the blockchain will grow exponentially in size. If we have 10X more transactions now, the chain size will be nearly a terabyte next year. Also, huge block size makes it difficult for miners to download, because all miners have to download the new block, before they could continue to mine.
No, you don't understand. The blockchain can only grow exponentially if the block size limit is completely removed (which it doesn't have to be). As long as a balance is maintained which allows for reasonable and competitive transaction fees, ideally on the order of a few cents in USD, we don't have to worry about high frequencey trade spamming.
And oh my god, nearly a whole TB in another year? Shit I only have 10 of those free at my house right now. Did you know that storage actually gets cheaper over time? Some Moore guy's rule or something. Too bad I can't run a full node on my phone, probably should constrain Bitcoin over it.
The block size limit doesn't have to be larger than what most miners can download with reasonable bandwidth. It just has to scale at some rate. All computing resources scale, our transactional capacity HAS TO as well.