Troops can currently wear non-American-made boots if they purchase them on their own (through allowances). That standard could change, however, as federal lawmakers consider the Better Outfitting Our Troops, or BOOTS, Act.
www.militarytimes.com

Inspectors at Camp Lejeune examined 4,423 boots and found 538 defective pairs, a failure rate of 12.17 percent; July inspections revealed substantially higher defects than April results, indicating notable deterioration in product quality.
Commanders purchased replacement M77 boots from local stores 'at a higher and unanticipated cost' to sustain training, as the Marine Corps confirmed observing 'out-of-the-box workmanship failures' firsthand during the exercise.
ground.news

Well, this is interesting.

2025 - The Marine Corps is developing new footwear after it found that a significant percentage of boots Marines were buying had quality issues, resulting in Marine Corps Exchange stores having to return nearly one-quarter of its boot stocks.
The Optional Boot Program, which was publicized in a service news release last week, is meant to quickly get high-quality boots to Marines through inspections, fleet feedback, real-world testing and industry competition after COVID-era supply chain issues began rattling quality and inflating prices starting years ago.

Having served as program manager for the CSS for two years, Gillikin said that he has received plenty of feedback from Marines about boot quality and cost, and that fit and durability are often top feedback points for footwear. The release from last Friday said that service-approved boots can range between $189 and $399 and, while enlisted Marines receive a uniform allowance, it often doesn't cover the cost of top-rated footwear.
www.military.com