I think major theatrical reissues were tapering off by the end of the 1970’s, except for revival theaters. Disney was reissuing their classics (every seven years) well into the 1990’s though. That is probably the model George wanted to emulate.

Star Wars was too much of a license to print money for Fox to ever make such a threat, especially if they wanted to distribute the sequels. The home video market was barely in existence when Lucas was quoted circa 1978. By 1982 it was already a considerable new revenue stream for the studios, and George has never been allergic to making money.