Modern Orthodox does not allow women to wear pants, or married women to go with their hair uncovered. I highly doubt you’ll find a MO Rav anywhere who would say it’s ok.
Are there people who do it? Yes, there are. Just as there are Jews of all types who speak lashon hara and motzei shem ra (such as the OP claiming that MO allows these things), Jews who steal from people, Jews who molest children… need I go on? Just because some people do it doesn’t mean the official stance is that it’s allowed.