Within 30-50% is close enough when you account for the fact Nvidia has an ~80% market share of PC gaming which translates into PC game developers and porters putting far more effort into Nvidia-centric optimizations if not outright using Nvidia-specific enhancements. Being the market share underdog by a wide margin is a major handicap.That's a huge margin of difference, not at all what I would consider "close enough".
This is similar to how Ryzen is technically superior to Intel on paper but Intel still beats Ryzen by often substantial margins in most games since game developers optimize for Intel by default due to Intel owning 85-90% of the desktop market for the last ~12 years. It took about two years for game developers to fix most major hiccups on Ryzen and another year after that for AMD's Ryzen sales to really take off.