Exactly! So why are pyjamas judgeable but t shirt and leggings not, when they are exactly the same thing?
They're different things. Most people don't sleep in leggings. So much slobbish behaviour is excused with 'but what's the difference'.
If you go out in pyjamas, slippers, a dressing gown etc, many people will judge you as lazy and lacking self-respect, or assume you have personal problems.
Having basic standards for yourself is a good thing.