As an engineering manager, I cannot imagine assuming that people would read something.
Engineering managers think horizontally in an organization, with enough depth in intra-team individuals and inter-team dependencies. There's a lot of similarities to software engineering: understand the product, know enough depth for what you're building, and understand dependencies on the edges.
Core pieces of these for an EM are fundamentals of human behavior, motivation, and process. There are global-ish truths about humans and global-ish truths about complex human hierarchy. For the former: individuals are more likely to get defensive when confronted in public.
For the latter: the same way there is a compounded risk of latency and failure with multiple network hops, there is a compounded risk of mis-alignment with multiple human hops.
I recently worked at a larger company (Stripe) where I was 5 hops from the CEO. Coming from startups, the information loss/skew between the CEO and my team was incredible. I found myself very much aligned with the CEO, which I could confirm by Slacking them. But by the time it trickled down to our team the incentives, motivations, and direction were mildly fucked. Navigating that is part of the craft, which we can feel any kind of way about but doesn't feel entirely avoidable.
"[X] will read [Y]" is a human fallacy, not simply a manager one. See: "just read the docs", "did you read the article you're commenting on", "the code is self-documenting", etc.