Wouldn't it be the opposite? I'd expect the code would be 47% longer because it's worse and heavier in tech debt (e.g. code repeated in multiple places instead of being factored out into a function).
AI isn't very good at being concise, in my experience. To the point of producing worse code. Which is a strange change from humans who might just have a habit of being too concise, but not by the same degree.
In my experience, review was inadequate back before we had AI spewing forth code of dubious quality. There's no reason to think it's any better now.
An actually-useful AI would be one that would make reviews better, do them itself, or at least help me get through reviews faster.
One: The work to get code to a reviewable point is significant. Skipping it, either with or without AI, is just going to elongate the review process.
Two: The whole point of using AI is to outsource the thought to a machine that can think much faster than you can in order to ship faster. If the normal dev process was 6 hours to write and 2 hours to review, and the AI dev process was 1 hour to write and 8 hours to review, the author will say "hey why is review taking so long; this defeats the purpose". You can't say "code review fixes these problems" and then bristle at the necessary extra review.
All source code is technical debt. If you increase the amount of code, you increase the amount of debt. It's impossible to reduce debt with more code. The only way to reduce debt is by reducing code.
(and note that I'm not measuring code in bytes here; switching to single-character variable names would not reduce debt. I'm measuring it in statements, expressions, instructions; reducing those without reducing functionality decreases debt)
I think you instead meant to say more business logic implemented in code is more technical debt, not necessarily just more code.