Ebooks sales are not that great.
The problem isn’t books, it’s publishing.
Guess who owns the publishing houses.
As for self-publishing...
Well, God made editors for a reason.
Are there some publishing houses that do not produce quality books? Of course. But books have been printed for hundreds of years and there are billions of them around from a myriad of publishing houses.
If you choose not to have them available in your house for the children to read, that is entirely on you.