I'm pro-AI and anti-regulation but I don't think it's wise to completely dismiss the reality that these things will lower the bar for bad actors to get access to dangerous things. The Tokyo sarin gas attacks are pretty relevant:
Asahara and 24 other cult members traveled from Tokyo to Perth, Australia, bringing generators, tools, protective equipment, including gas masks and respirators, and chemicals to make sarin. ...the group chartered aircraft from Perth to Banjawarn Station, where they searched for uranium deposits to make nuclear weapons and may have tested the efficacy of the synthesized sarin on animals...The group left behind several drums of hazardous and toxic chemicals, and empty bottles of sake strewn about the property. Following news of the subway attacks, the new owners became suspicious and contacted the Australian Federal Police, who inspected the property and found evidence of past chemical weapons testing.[24] Despite the safety features and often state-of-the-art equipment and practices, the operation of the facility was very unsafe – one analyst later described the cult as having a "high degree of book learning, but virtually nothing in the way of technical skill."
(https://en.wikipedia.org/wiki/Tokyo_subway_sarin_attack)
How much more damage would they have done with a small amount of help from a capable LLM?