So I've found that among the many stack exchanges I frequent, there are many new users (yay!).
When I was first on the Stack Exchange site, I was greatly helped by a user (@ColleenV, if memory serves me correctly), who pointed me to the site tour and help pages.
I have tried to "pay it forward", but I'm not always successful. In the latest failure, which prompted this post, myself and multiple other users had a long chain trying to coax information out of a new user regarding their question, before determining that it was off topic, and trying to explain this to the new user. The comment thread was moved to chat before it occurred to me or anyone else to direct the user to the tour or other pages.
Therefore, I propose we have an automatic comment appended to first question a new user makes, or perhaps questions made while their reputation is below a given threshold, which would direct them to the relevant tour, help, and on-topic pages (to make things simple, we could tie it to the "new contributor" flag), rather than leaving this to fallible users.
Additionally, if a "new" user has sufficient reputation from another stack exchange site, to point them towards the on-topic page, since that changes between each stack exchange.