re: Why do home renovation contractors never follow up on providing quotes?

I don't know you personally, but I can tell you that most sub contractors are pretty busy these days, and when they do a walk through with a customer who they think will be troublesome/a nag/ annoying/ a know it all/ a pain in the arse/ hard to deal with, or all of the above, they smile when they leave and know before they start the truck that they will never see you again because they don't want to deal with you and don't need the work.
If they were not busy it would be a different story.
A wife with auto cad drawings is a wife who will likely boss them around and look over their shoulders during the job and tell them that they're not doing it correctly.

Think about it....they do this work for a living and you call them for a job and are willing to pay.....what else can it be?

They can pick and choose which customers they want.
And they don't want you.