BIP 300 and BIP 301 are two BIPs that allow for the creation of trustless side chains. You keep the maintain unchanged. However, you get more scalability options and features with your bitcoin. You simply send your bitcoin to a sidechain of your choice. Some side chains optimise for payments, others for smart contracts, others for end-2-end encrypted private transactions. Miners get all the fees from the transactions on the side chains. Lightning is vertical scaling. Drivechains is horizontal scaling. I think it would also kill shitcoins or at least help increase bitcoin dominance. As it would make all “bitcoin competitors”, smart contracts alt coins and privacy coins pretty much useless. As you would now be able to do all on bitcoin side chains. Bitcoin would be the native currency of these side chains of course. Does that help? Look at drivechain.info or layertwolabs.com for more.