From the first sentence of the article: 8.4%

So, roughly 2,000 employees?

Original post: https://ma.tt/2024/10/alignment/

Edit: I stand corrected. OP is asking how many employees are in the WordPress "division", which I cannot find a public source for and is kind of hard to tally.

Matt said yesterday[1] that ~100 employees work on wordpress.org, one chunk of what encompasses the WordPress "division".

1. https://news.ycombinator.com/item?id=41726197#41726796