The difference is that nukes and - in most countries - guns are harder to find. Regulation is easier when you have more centralised distribution channels. Code is infinitely replicable at marginal cost, and so highly accessible once it's open source.
While I agree with you that the net effect of such technology will be negative, there's no way regulation can keep up.
I'm not sure the net effect will be negative. Cheaper and more follow along audiobooks for people with dislexia, a voice for people who lost their own. Lots of bad stuff too sure. But your first point is spot on. There is no stopping it. AI has come to replace all creative endeavors with poorer quality regurgitated substitutes leaving human created things as a luxury for the wealthy... Except people will not stop singing, painting, writing, or coding and too many people enjoy doing those things for the price to ever go too high. Except law clerks, and contract lawyers. They will probably just go away, but now they can pick that paintbrush up, or get the band back together. Or code up an unauthorized sttng game with synthetic vocals for picard.
While I agree with you that the net effect of such technology will be negative, there's no way regulation can keep up.