My lawn would be so long if I mowed every other week. It would also be extremely bad for my lawn (fescue with KBG and rye).
I mow about twice a week and keep my lawn at 3” - 4”. I like it a bit longer.
If I let it grow for 2 weeks I’d be chopping off 50% or more of its length which puts the lawn under so much stress. It would be wide open for disease and it would actually be wasting water.