SUPERTECH 5w-30 longevity?

My dad drives a 2010 Honda Accord with the basic 2.4l 4-banger and drives about 100 miles a day, for five days a week… Now all he uses is SUPERTECH 5w-30 and he changes it at 6-8k miles when the Honda "oil/maintenance" light comes on. Keep in mind this is DINO or conventional oil. Is he harming his car following the oil change minder over the 3-5k lifespan of typical conventional oils. Both my parents act like its no big deal oil is just "oil" I never believed that. So thought I'd ask you guys with more knowledge and experience. I always use Liqui-Moly or Mobil 1 Extended Performance for my vehicles but. Anyways?

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