Self replication is trivial. All you need to do is copy the files and run it, just like any other computer program. LLMs have been capable of doing that for a while now. It's not a real concern.
Not long after every lab started bragging about involving AI in the development process, oddly enough.
I recently informed GPT-5 of what GPT-4 helped me build back in the day (a self-modifying Python programmer) and it became very uncomfortable.
Claude shut down my chat last year when I asked about "living information systems". It was a philosophical question, but god knows what branch of the safety classifier I tripped.