[josephpoon]

>Instead I'd rather see people try to fix the problem of it being expensive to spend bitcoin sourced from many small inputs.

Lighting does this. With a single blockchain transaction, you can conduct as many micropayment transactions as you desire with anyone else this network. After the first funding transaction (which is broadcast on the blockchain), there are no more blockchain transactions until you wish to settle the channel. All micropayment transactions are deferred and net settled on channel closure. Your current balance is updated off-blockchain securely with real bitcoin transactions (which current state can be broadcast at time by either party).

>So if the lightning network does get build, we'll all be able to use microtransaction channels which will slow the growth of the blockchain, but will still cost $20 in fees to send $100 worth of bitcoin sent in tiny UTXOs.

It'll probably cost a lot to set up the channel and to close it out, but you'll only do that once and it can last for years. It's equivalent to setting up a bank account. The actual day-to-day payments are off-chain (without counterparty risk).