When I heard about this I mentioned it to my son last night when he got home from work. It's not just good marketing, they would be negligent if they didn't do it.
The message from WotC will be clear, you have enjoyed D&D for 50 years now and THIS is the ultimate edition. Then third quarter (or even fourth to get that Christmas dollar) D&D 5.5 will hit the shelves.
They can spend the first two-quarters of 2024 hyping D&D from its roots and evolution. I have been saying EVERYWHERE that WotC will not do anything until the 50th anniversary of D&D in 2024.