Pashuteh Yid-Some people find a shirt very bothersome, so surely you’ll be maskim I can daven without one.
I love how some modern folks will make every kula necessary to get what they want. To daven without a hat and jacket in shul is disrespectful to oneself, disrespectful to the shul, disrespectful to the mispallelim, and disrespectful to the RBS’O.