I have a collection of several hundred T-shirts. The oldest one is from a then-popular but now-defunct restaurant in my West Texas hometown, obtained in the mid-1980s. Still fits, sort of. Although I have graduated to 2XL, many of my XLs still fit. The ones that don’t tend to come from Asia, where even a 4XL would often barely pass for M in the West. I too collect them from my travels, organizations etc. I dislike T-shirts with mindless slogans like “Keep On Truckin’” etc.