Like many people I have concerns about the use of 0W20 lubricating oil and its effects on engine longevity.
Is 0W20 oil a concern? Its low viscosity is specially suited to modern engines with precise engineering tolerances , and circulates more quickly from cold. Its has advanced additives ,some of which help extend its longevity in service (should service intervals be extended or neglected) and made to quality standards which may not have been possible a few years ago.
IMO the main concern is when 0w20 oil is NOT used (or an older specification 0w20 missing some additives). The idea that a thicker oil is more 'oily' or somehow fills increased clearances on high mileage engines is perhaps outdated. Something like 80% of engine wear occurs during the first few miles from a cold start. Cold ,thicker, oil takes longer to reach and lubricate moving parts extending the period of unfavourable high wear conditions. But other opinions are available.

Maybe the thicker oil also takes longer to drain down , leaving parts with a coating of oil. And those who do high mileages tend to do most of their miles with a hot engine.