I wouldn’t be comfortable with a 38 minute MCT and whenever AA changes my flights resulting in a tight MCT, I call and get different flights. I actually enjoy a relaxing layover of a few hours in the lounge or just getting some exercise walking around the terminal since all of my flights are transcons and long haul internationals. I really hate the stress of having to rush to make a boarding call. They start boarding at least 30 minutes before departure and with a 38 minute connection, even in the best of circumstances at a major multi terminal airport you are seriously pushing it.