Frankly, Joel lied in his response to you.

He has been frequently challenged on Twitter. He routinely blocked those who pointed out flaws in his analysis instead of engaging in debate in good faith. An example of this was when people pointed out that his baseline for all-cause deaths was generated based on a very narrow, unrepresentative set of sample data.

An example thread is here: Joel blocked the author instead of engaging with him. This was clearly not a "hit piece", as Joel claims. https://twitter.com/_johnbye/status/1365650853252771843

Whatever side of the debate you're on, Joel's approach to debate of his claims is extremely unscientific.