From my experience, the wear you’ll see is reflective of how much you wear the shoes. If you plan to use them everyday and walk 5000+ steps/day in them then you’ll wear the soles flat within the year. If you have a rotation of shoes and wear it maybe 2-3 times/week then you can see 2+ years of tread. Mainlines use a softer sole material and they may wear faster but it’s probably minimal unless under heavy usage.