What can be stated without evidence can be dismissed without evidence. It is IMO pretty clear to me there is no substance to this post, without knowing anything about the author.

In general most such claims today are without substance, as they are made without any real metrics, and the metrics we actually need we just don't have. I.e. we need to quantify the technical debt of LLM code, how often it has errors relative to human-written code, and how critical / costly those errors are in each case relative to the cost of developer wages, and also need to be clear if the LLM usage is just boilerplate / webshit vs. on legacy codebases involving non-trivial logic and/or context, and whether e.g. the velocity / usefulness of the LLM-generated code decreases as the codebase grows, and etc.

Otherwise, anyone can make vague claims that might even be in earnest, only to have e.g. studies show that in fact the productivity is reduced, despite the developer "feeling" faster. Vague claims are useless at this point without concrete measurements and numbers.