The ASOS record began in 1996 and exists primarily for air traffic safety. For example, if the RVR, vis, CHI, wind, or pressure sensor (especially class 1 stations if any still exist) goes bad, it's getting addressed pretty quickly. If a temp, hum, or precip sensor drifts, it'll get fixed whenever because it's not critical to aviation. A lot of the disputes here are less about siting and more about suspicious measurements. The climate record even at the first order sites are mostly stitched together through time anyway using nearby stations and differing equipment since the climate records go back before airports.