I don't think we necessarily need the same security as we have now. Bitcoin's hashrate has been on a more-or-less steady upward climb since day 1. It wasn't 51% attacked when the price was 3x what it is now with half the current hashrate, and it wasn't 51% attacked when the price was the same is it now but with double the block subsidy and only a tiny 5% of the current hashrate. It's about making sure the fees ensure the network is secure enough, not that the hashrate continues to increase forever more.
When the price was 60k, a s19 was 10k , a cool 100$ per TH/s, right now you can buy the pro for 19$/Th/s with next day delivery.
Back in April, you couldn't attack the network because there was no gear to buy, right now you have tons of both older gear that is not feasible to mine with and tons of new gear that isn't being bought and tons of orders
getting canceled so you have that one click away.
So it's not about how big the hashrate is, it's about how much it will cost an attacker to take over it, no entity is really feeling threatened by a system with the marketcap the size of Nvidia and with 200k daily transactions, when it reaches 10x times that, do you think $20millions a day will be enough to repel an attack?
Hence my comment about multi-user channels. If you could open a channel which includes 20 users, they can all pay $2 which is fine for the user, but the miner earns $40 for that channel being opened.
It's all good on paper, and of course, almost everyone here (except for franky1) would use it, but you think the average Joe who is angry at banks for taking him 1$ a month for card maintenance will be the one opening and closing channels like that? Make it ten cents and then we talk
More concerning it that we're nowhere near having full blocks actually as on-chain transactions are going down rather than up for the last few years.
Then we need more adoption and more use as a currency!
Of course, we need more adoption, we need more spending we need usage, not fancy bitcoin towns, laser eyes, and Vulcano bonds, but all those memes about holding two satoshi cause in 20 years you're going to buy an island with it are definitely hurting actual usage.
Fortunately enough there is an almost certain failed experiment happening right now with ETH and I'm pretty sure in a few years we will have plenty to learn from what happens when people just store money in order to get more money out of thin air without doing a thing.