I'm also running into this issue with the 14.5 RC/Public release, frustratingly it also seems to affect production apps compiled with the 14.4 SDK running on iPadOS 14.5
The only workarounds I’ve found are embedding the NavigationLinks in a List or Form, though both apply a number of style and behaviour changes to their children which prevents me from using this approach in production.
If you file a feedback/radar feel free to reference mine FB9091466, likewise if you have already done so I'll append yours.
I've uploaded my sample project here for anyone interested https://github.com/tomhut/navvy/blob/master/navvy/ContentView.swift