There are many great ways to buy shirts for $20-25. From online stores to Cosco, I rarely pay more than $25 for good quality, good design shirts.
Another great way to live more simply is to live more simply, and among others that chose to live simply as well. It’s very difficult to move, but if you find that materialism in your local community is overwhelming, this may be a worthwhile option to consider.
This was a major factor in our decision to make aliyah. Our kids don’t ask for the latest and greatest in fashion or tech, because the culture and community we chose to live in doesn’t talk much about fashion or technology. Most people in our neighborhood work hard for their parnassah, but life is just simpler than we had in the US. Simchas are simpler, cars are a bit older, clothing is usually a bit more tsanuah (in the traditional sense of modesty, not just necklines). Moving wasn’t easy, but it has in many ways defined us.
Bhatzlacha in your journey.