The first
Mitsubishi's 1996 Galant GDI in Japan was first to mass-produce stratified-charge gasoline direct injection. In the US, Volkswagen's 2.0 TSI (2005) was the first widely-sold direct-injection gas engine.
The rollout
By 2010, GDI was standard on most premium-segment engines (BMW N54, Audi 2.0 TFSI, Ford EcoBoost). By 2020 it was standard on essentially every new gasoline engine sold in the US — port injection had become the exception.
The carbon-buildup problem
Direct injection sprays fuel into the cylinder rather than across the intake valves — which means the valves never get the detergent wash that port injection provides. By 100,000 miles many GDI engines develop carbon deposits on the intake valves heavy enough to cause misfires. The fix (walnut-blasting) is a $400-800 service that didn't exist before GDI.
The point
GDI bought the gasoline engine another decade of relevance — better fuel economy, more power per litre, lower emissions. It also created an ownership cost that was new in 2010 and is now routine. The trade has been worth it.