Why "exclusive"? Because George Lucas famously called the original negatives "unfinished" and spent millions altering them. In 1997, he declared the Special Editions the "official" versions. The original theatrical cut has never been released on modern Blu-ray or 4K.
Not the Special Edition. Not the 1997 "improved" cut. Not the DVD version with the questionable Jabba CGI. star wars 1977 original version exclusive
Whether Disney eventually capitulates and releases an official 4K version is almost beside the point. The preservationists have already done the work. They have ensured that in a galaxy of constant updates and reboots, the original vision of that twin sunset on Tatooine remains preserved in amber, waiting for anyone willing to look for it. Why "exclusive"