It appears that the parent company of Universal theme parks only has until 2025 to create new Harry Potter based theme park attractions. According to this article, linked below.
"NBCUniversal in 2016
inked a rich seven-year rights deal with Warner Bros. Domestic TV Distribution that included U.S. broadcast, cable and streaming rights to the Wizarding World franchise. That deal, which ends in April 2025, included digital initiatives as well as theme park content and events."
Source:
'Harry Potter' Live-Action TV Series in Early Development at HBO Max (Exclusive)
Of course they could extend the contract, but I don't think universal would want to lose the right to do this. Maybe this is hope that Epic Universe will be built by then? And possibly a small addition to the existing Wizarding Worlds will happen in the next few years, too.