There seems to be this continuous idea that relationships are designed egalitarian however this is just false

Most relationships always have the SO putting less effort, which happens in many areas:

Finances

Communication

Sexual compatability

This is due to the fact they know there's always a safety-net if it goes south and for most women, it's usually backup guy nr2 while for most men no one, that's why they love lumping on this idealism

Like most things in life, there's never an equal input, relationships are no exception to this rule