In these days ETH gas fee will down to 5$ per transaction why this happen?
There was even $1 at a time, but not for long. Obviously, the ETH network has been heavily spoiled by third-party directions in the ecosystem, such as DeFi or NFT. If you think back to what transaction prices were in the summer of 2021, it's clear that it was because of NFT trading on OpenSea. Look at OpenSea trading volumes now, their volume has dropped dramatically, hence the load on the Ethereum blockchain has dropped, as has the price of gas. There is a pattern to all of this.
Unfortunately, it is a self-increasing problem. Meaning that if it goes down, more people see it, and more people invest into it and more people start to spend more on gas fee and it increases all over again. I am not saying that it has to happen, just that it has been what happens so far in the past and I can see it happening again this time around as well.
Hopefully, it doesn't happen but I believe that the same thing could happen during this period as well. This is why I believe that 1-5 doesn't matter, it will always go back to 10-20 but then eventually it will go back to 5-1 levels and then it will go up and that is why it will never be stable.
Maybe switching to PoS will solve this problem to some extent. Commissions in the ETH network have long been an acute problem, they are very expensive, especially if you take the interaction with smart contracts as an example. It's just a rip-off, hundreds of dollars per transaction, that's a lot.
I think the problem with higher commissions disappeared for a while because the hype for different tokens that interact with the ETH blockchain subsided a little bit. But if the hype around some tokens starts again now, the problem will easily repeat itself, over and over again.