For every heavenly high, there’s a hellish low: What’s really BAD on that leading blockchain that you love?

Hey, guys.

I'd like to gather from you, whether you are a developer or holder, some major flaws about that leading blockchain that you hold and shout "to the moon". I want to know what is really BAD. I meant BAD. Show me the demons! There's no way to be like heaven all the time. Something must look like hell.

I'm sure you all know the confirmation bias. It's a cognitive trap that makes it easier to choose the information that just backs your beliefs. If you want to buy Ethereum, you will normally focus more on people telling you good things about it than those saying bad things. So I'm seeking other perspectives that might challenge my understanding.

I've started my journey to become a developer and I recently contributed to the build of a blockchain resource library (here if you are interested in contributing). I helped with Optimism and zkSync. Now I'm working on Cosmos (hey, Cosmos fans!).

When I talk to devs/holders, they only say nice things. It looks like nothing is ugly. Solana, Polygon, Arbitrum, Cardano, Astar… all of them have something that is "the best of".

So I would like to gather here some pros and cons of leading blockchains. I'll start with the ones I contributed:

1. Optimism – Pros: Scalability and fees. Cons: Adoption (?),
2. Cosmos – Pros: Interoperability. Cons: Fragmentation.
3. zkSync – Pros: Security. Cons: Complexity.

So, there's got to be a few digital demons lurking on your favorite blockchains. Which are they?