Personally I'm not even sold on the current paradigm being too limited to produce AGI - there are still several OOMs worth of compute increase available, plus the algorithmic improvements have overall been accumulating faster than predicted.
But even assuming that a major breakthrough is required, it seems ludicrous to me to go from that to a timeline of a decade or more. This isn't like fusion power research, where you spend 10 years building a new installation only to find new problems. Software development is inherently faster, and AI research in particular has been moving extremely quickly in the past. (GPT-3 is only 6 years old.) I don't think a wall in AI progress, if one comes at all, will last more than a few years.