Why

Currently, Monero only has one node written in C/C++, many would see this as an issue. Having only one implementation makes us more vulnerable to implementation bugs, having another node will help us to spot and fix these issues.

monerod's code is also a bit of a mess, as many devs who have worked on it would agree. Cuprate is a fresh start and is built with modularity in mind which will lead to a cleaner and easier to understand codebase.

Having a consensus rules document will make it easier for developers to build software to interact with Monero. It will also make it easier to spot potential issues with consensus rules.

Popular documentation like “Mastering Bitcoin” suggests the usage of bx seed for wallet generation.

Secure cryptography requires a source of large, non-guessable numbers. If the random number generator is weak, the resulting cryptographic usage is almost always compromised.

For technical people: in this case, practical wallet security is reduced from 128 bit, 192 bit or 256 bit to a mere 32 bit of unknown key information.

I am not an expert, but if you use a multi-coin wallet that includes Monero, then your Monero could be affected. I don't see a list of wallet software that is affected. It would not be easy to verify that closed-source wallets do not use the exploitable code library.

Q: I used bx to generate my wallets but only use it for non-BTC coins, do I need to worry?

A: Yes. All funds stored on BIP39 mnemonic secrets or BIP32 wallet seeds are affected since the underlying private keys are basically public now.