Years ago, I emailed a question to the church about its teachings on some subject (I no longer remember the topic).

Reply: "we will be happy to send a missionary to your house to explain this."

But I suspected that the church absolutely did not want to put anything in writing, in the event that its teachings changed; so to get around that problem, it would be happy to send a missionary, so that if the teaching changed ("revelation"), it could say "well, the missionary was probably young, misunderstood the teaching" and so on.

So I replied (email) "I'm a little hard of hearing, and anyway I absorb things better in print."

As I expected, I never again heard from the church.

was curious to see if the church would give me anything in writing--since I suspected that it wanted to

You're absolutely right. They've finally put some things in writing though they don't say that they were approved by the first presidency.

Here's some things you might find interesting. https://www.churchofjesuschrist.org/study/manual/gospel-topics/intro?lang=eng

People who sell ignorance as bliss send their most ignorant (youth) to answer all the questions. It is way more successful than one would think.

Their old dissimilate, their young proselyte.