The problem with bigger block sizes is that it increases centralization as it makes it harder for ordinary people to have their own full nodes. Additionally there is no limit to the requirements the network will need on block sizes because as you increase them and transactions increase you will keep needing to increase them and there is a limit to how far you can go.
A long term solution would be based on offchain transactions and other things to reduce the clutter that is why people propose segwit and lightning network. Personally I think we are at the point where 2 mb hardfork is a necessary compromise since certain people dont want to signal segwit (even though it almost doubles the block size all by itself), but segwit is a must because we cant keep increasing block sizes indefinitely.
Nonsense. You are thinking that txs will suddenly jump from 300,000 per day to 10,000,000 per day. It is perfectly safe to increase blocksize. It's the Core dev that got ideas of their own and sod the rest of us.