As of late since the Patch Seek And Destroy has come out, there has been a HMD issue where it either displays only in certain places, doesnt display at all, or disappears once you look around. (F-16C and other Aircraft have this issue)
This has yet to be fixed since the update dropped and its getting extremely annoying as its a very useful tool to use while in a Dogfight.
Note this screen recording is very very compressed, and this is the latest version on war thunder on the PS5.
Version 1.000.257