It’s not instant it takes a long time until enough confirmations have been done. It’s not even clear how many confirmations are enough.
You’re thinking of main chain (which takes 10 minutes for the next block), though I would take a zero-conf transaction in any situation that isn’t moving more money than a day’s labor. A single confirmation means it made it into the next block which should be plenty for 99% of situations. If you’re selling your house, maybe a wait a 2-3 blocks to be sure. Lightning is instant and uses main chain for security but does settlement/transaction data off-chain.
Lightning network is literally a traditional bank transaction mechanism on top of bitcoin.
It’s not, you don’t need a bank to use it. Banks don’t settle instantly, banks have chargebacks, banks required six forms of ID, banks can’t reach some places, banks may discriminate. Lightning is Bitcoin. You lock up BTC in a lightning channel, you can then send that BTC to anybody via lightning, and when you close your channel, you get the appropriate amount of BTC back. You can run a lightning node on a phone, a “routing” node on a raspberry pi, it’s just as decentralized and trustless as the main chain is. You can open a channel directly w the person you’re transacting with or you can forward the transaction through other channels/nodes, all trustlessly, all instantly, all automatically. Nobody ever has custody of the funds aside from you and your intended recipient. There’s no central custodian (like a bank) you have to trust.
If you are arguing for using lightning transactions, what is the point of bitcoin in the first place?
Main chain and lightning have different use cases. Use main chain for long-term storage of funds or large transactions. Use lightning for everyday spending. Main chain secures lightning transactions. Main chain is layer one, lightning is layer two, it’s possible there will be more layers, just like SMTP is built on TCP which is built on Ethernet or whatever.
fees are huge and will only increase in the future.
Main chain fees are around $1.50 for the next block, which is still cheaper than a bank wire or other equivalent payment methods in many situations. You’re right though, they are expected to increase as adoption increases, but lightning has scaled that available blockspace several orders of magnitude. Lightning fees are <1% in almost all instances and aren’t expected to increase since they are not tied directly to main chain fees and no mining is required. A lightning transaction uses about as much CPU power as sending an e-mail. A single main chain transaction can open a lightning channel. You can have billions of transactions inside a lightning channel.