Praying is obligatory and is one of the pillars of Islam. Covering of one’s ʿawrah is also an obligation that one should try to observe as far as possible. However, not being able to fulfil one act does not nullify the other, as these are separate obligatory acts.
It is not up to humankind to decide if one’s acts of rituals, faith and goodwill are futile or otherwise. Everyone has their own struggles they need to work on in order to become better Muslims. Let’s hence focus on ourselves, and leave matters beyond us to God, the All-Knowing.