Network downtime

How often has the ethereum network gone down or run into problems (besides gas fees and theDAO)? As much as people like to compare it to SOL, I've read in an article that it has had some network issues in the past but I don't know where to look for where this happened

https://river.com/learn/bitcoin-vs-ethereum/ (Keep in mind this is not a direct comparison of the 2, as even in the beginning the article states that the two have very different goals and use cases.)

"On several of these levels, Ethereum has shown itself to be more centralized than Bitcoin. This centralization has revealed itself through network downtime and arbitrary changes to the protocol."