Thats a bit cynical dont ya think? I highly doubt that in 1977/78’, during his interview about his target audience, that he had the forethought to be that egotistical.
Sure, it’s cynical, but I still think that even young Lucas had a habit of presenting himself the best way possible, not as much as in his later years, but this behavious surely didn’t came from nowhere. So whenever things worked out in his favor, intentionally or unintentionally, he sold them as part of his “original vision”.
Regarding your original point, I don’t agree. I saw the OT at the age of 8, TPM at 10, and AOTC and ROTS at 11 and 14, respectively. And while I loved all these movies the first time I watched them, only my love for the OT, and Star Wars in particular, lasted for more than 2 or 3 years. So while Star Wars appeals to children and adults alike, the PT is intentionally aimed at children/teenagers, but loses this appeal for many people when they grow up.