(parent edited)
> Then, why not make it bigger?
To what end? They were lifting bombs on kites as early as the 7th century, as well as humans as novelties (and punishments - https://en.wikipedia.org/wiki/Yuan_Huangtou).
If you want a lift a human to do something, you also need some better steering and safe landing, and those require more reliable engineering besides just the basic lift possibility.