"It sells a $300 experience for under $100, and delivers on the price."
The "Big and Tall Gamer Chair" claim is marketing. The 18.2-inch wide backrest is narrow for larger frames, and the 400lb rating is a stress test number, not a safe daily-use capacity.
This is a decision for those prioritizing the 'gamer' aesthetic and a sub-$100 price tag above all else. It functions as a temporary or low-use chair for smaller individuals who accept it may need replacement in 1-2 years.
Anyone genuinely big, tall, or weighing over 250 lbs should ignore the marketing claims and avoid this chair. Buyers seeking durable construction or actual ergonomic support for daily work or gaming will find this a poor investment.