PSA: You should be wearing tall-sized shirts
A standard-length small, medium or large may fit your torso, but it is not long enough. Every time you raise your arms above your chest you are flashing your midriff, your short sleeves often look comically short; you look like a short person wearing a kid's size.
You should only wear tall-length shirts, especially if they're untucked. Yes, this means you are very limited to where you can shop and will usually need to buy clothes online. Accept it. Find styles you like at places that do you have your size. No matter how nice a shirt is, it does not look good if it does not fit you. This is the price we must pay for our gorgeous tall bodies. This is our burden.
This may be obvious to some, but it has taken me (33m 6'4") a long time to understand and fully accept. I wish I had more options, but accepting I don't and wearing what's fit me has improved my look and made me feel more comfortable in my clothes.