That's incorrect. Mining will still be required it just means instead of block rewards driving miners it'll be transaction fees. Bitcoin will never not require miners because they provide the entire validation/verification process for transactions.

I think the confusion is because the mining analogy makes people think miners mine Bitcoins, when they actually mine blocks.

And whos going to create the blocks? It's still mining. However, tx fees might not be enough to pay for security in the network.

I didn't think of it that way, but you are very correct.

It irks me that the wastefulness of bitcoin is proportional to how valuable it is, and I don't think that changes even when miners are only competing for transaction fees.

edit: Waste might even be exponentially proportional to bitcoin value...?

In economic equilibrium, the world-wide energy cost to mine one block would be approximately equal to the revenue from mining the block (transactions fees + newly generated bitcoins).

There will still be mining, just no block reward. The "payment" would instead be solely from transaction fees.

If we make the transactions more efficient, lowering the fees, we might remove the huge incentive to mine so much. That would be great.

This is nonsensical and wrong. Transactions aren't what causes energy consumption in Bitcoin, you can process all the transactions in the whole Bitcoin or Ethereum network on a Raspberry Pi. It's the proof-of-work hashing that makes Bitcoin energy-inefficient, and that's purely a make-work problem, just a way to make mining arbitrarily difficult so the block times hit the expected average.

The problem with scaling to larger numbers of transactions is that block sizes become bigger and it takes more disk space and bandwidth to run a node. But, the bigger we make them, the more transaction fees there are, so incentives for miners would actually go up.

(very marginally so - block rewards are like 100x as high as the transaction fees, which actually leads some miners to not include transactions at all - trading off a 1% lower payout for faster propagation times and an increased chance of "winning" if they successfully mine a block at nearly the same time as another miner)

Maybe I wasn't clear in my original message. I meant that with lower block rewards and lower transaction fees (through lightning and other advances), the total reward for mining would go down, removing the incentive for the large number of mining operations.

On the large scale, I don't see mining efficiency affecting total bitcoin power usage, but I do see rewards impacting it. (higher BTC price => higher economic incentive to mine => more investments in mining operations => more power usage)

I think a lower bitcoin Hashrate would actually be a good thing (for power consumption and pollution)

Bitcoin is entirely arbitrary. Given that the concept of cryptocurrency (as a get-rich-quick scheme) has been proven, there's nothing stopping people from creating another one. And then another, and another, and another. The problem really is with the whole concept of cryptocurrencies.