Given the history of Ethereum, what could go wrong with a movement to proof of stake?
https://notes.ethereum.org/@djrtwo/risks-of-lsd
https://research.paradigm.xyz/staking
Another area that is new and can be biased is RANDAO:
https://eth2book.info/altair/part2/building_blocks/randomnes...
There are probably going to be several issues that will arise during and after merge, and might require engineering solutions.
Have a look here: https://twitter.com/web3isgreat
Centralization.
This has always been a problem with Ethereum and 'the merge' doesn't solve that and it will just continue to go down that route and will increasingly be that way.
As for a use-case, the only one which makes sense on the blockchain is something like what ENS does [0] which even some products have been built on top of that like Skiff [1].
But on this site to be honest you are not going to get a clearer, balanced and direct response that isn't on either extreme or screaming absolutist claims in both for or against crypto.
World wide sending cash without identity verification is not enough good use of Blockchain? Or you will try to sell me an idea that verification of everybody and all kinds of third parties is crutial to my wellbeing?
Yes there are many, many ways to solve that problem (tickets) without blockchain. As a software community, we invent how many JS frameworks that end up with the same exact outcome of dynamic web pages? A quick search says 83 with a top result of some article about "Top 40 JavaScript Frameworks". We jokingly hate on stuff like that but the vitriol about blockchain is odd. The argument that its not needed to solve X is fine, in software nothing is really necessary and there are a plethora of options with known solutions. Hackers/engineers are known to over-engineer things and do things just because they can.