It's like if you took some of the challenges of waymo and made them even worse. I imagine it'll take a similar amount of time to get there (although waymo still hasn't rolled out anywhere 'unpredictable' e.g. Naples, Istanbul, Mumbai).
Self-driving is a great parallel. Whereas the tricky part of self-driving are the edge cases, maybe 5% of what the car needs to handle. What DIY plumbing I've done tells me is that plumbing is just about nothing but edge cases, with 5% being standard stuff that an LLM might be able to handle.