How do you know warranty claims for this are routinely denied?Warranty claims for this are routinely denied, even after escalation. Even more fun when they discover sunroofs aren't included in a glass coverage rider (if you have one), but under their comprehensive policy.
Like I needed another reason to never get a car with a sunroof.
The WSJ article you read is about nearly 2,800 NHTSA complaints since 2021 involving unexpectedly exploding/shattering sunroofs, across 17 manufacturers and more than 200 models. The earlier NHTSA investigation that began in 2013 accumulated more than 4,000 reports before NHTSA closed it in 2021.