A friend of mine told me "tee shirts and blazers are dead." He was right except for the fact that he was completely wrong.
Spring, summer, and fall (and winter if you live south of the Mason Dixon line) are the best seasons for tee shirts and blazers. Elevate your vintage rock tee. Relax your double vented tropical wool sport coat. Everyone wins!
Here's the bigger point: no one should tell you what's "in" or "out." Wear white in winter. Break out your boot cut jeans. You should draw the line at Crocks with socks, but maybe that's you're thing.
When you fumble around your tee shirt draw looking for something you hope everyone likes, then you've lost. Fuck the Fashion Police. You be you and wear what you want.