The "Beta" personal menu item should only be shown for users who opted in to at least one beta feature. (I mean genuinely opted in, not including the users who merely did not opt out of default beta features.)
The personal menu can already be rather crowded (the default 6 items, ULS, Echo, LiquidThreads, sandbox links from site JS, and I'm probably missing some), and the "Beta" itself can become a *lot* longer in translations (the expression "beta feature" is not directly translateable to many languages).
I have once in the past created a superficially similar thing in site JS on pl.wp – a gadget preferences manager which added its own special page, which was linked from the personal menu – and I was promptly and bluntly told to get rid of that link. (It is now only linked from the Preferences pages and descriptions of each gadget that uses it and everyone is happy.)
(Personally I would consider this – or some other solution to the crowdedness issue – a blocker to wider release.)
Version: unspecified
Severity: major