That's part of the reason my car is split port/direct injection, port injection sprays fuel over the intake valves and cleans them automatically.
VW definitely isn't the only company that has had issues with carbon build up, but they have been using direct injection for a lot longer than most companies. There's a few articles online showing the FA20DIT (2015+ WRX and Forester XT engine) is showing significant build up pretty early in life.
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