If lack of DP2.1 prevents you from getting one be my guest for me it doesn't matter one bit lol. Would it be nice if it had DP2.1? Absolutely, but given that DP 1.4 can already achieve 4K240Hz anyway, it doesn't matter. And don't even try to...
DisplayPort supports audio and it's royalty-free. DP can do everything HDMI can do, only better. Unfortunately, HDMI beat DisplayPort to market by 4 years and was already rooted in the industry.
Price is ~1.500$:
https://www.trustedreviews.com/reviews/asus-rog-swift-oled-pg32ucdm#:~:text=ground in Cologne.-,Price and Availability,expected given the lavish specifications.