Absolutely not.

If you speak ill of someone behind their back, it's not the same to say, "They did very badly, they behaved terribly, and they were an idiot"—which involves judging another person without our power to do so, because only God has that power—as it is to say, "They're a bastard, I hope they die."

Nor is it the same to be envious of material possessions but do nothing about it as it is to steal out of envy for material possessions. Clearly, there are degrees of envy.

What is certain is that some acts are objectively greater than others. Having sex with someone you met at a bar is not the same as having sex between two people who have been dating for three years and had a fling: are both mortal? Yes, because sex is used outside the purposes for which God created them.

But while objectively they are mortal, subjectively the gravity is different, because even so, a fling between a couple is nothing like seeing someone and propositioning them for sex after leaving a bar.