If we're going to talk science and UFOs there are a number of obstacles. First, 95% an investigation occurs after-the-fact. You to the location, talk to the witness, go back to the location at the same time, check flight logs, star charts, and so on to determine if what they saw has an explanation. Most of the time the object is identified. You're at the mercy of the eye-witness, whom you must pay attention to so you can determine if they are being honest, and that takes a long conversation where questions are carefully asked.
That other 5% might have video of varying quality, and maybe some radar. Even then there is a lot of sifting through the tech. Cameras can record stars and airplanes at night. Radar is not the slam-dunk UFO cultists believe it it. And this is all still after-the-fact.
UFO cultists pick on science because the big missing piece is a UFO passing into an area where scientific sensors are waiting (like the end of Close Encounters of the Third Kind ). The USAF, Raytheon, Sandia Labs, and White Sands has places where that could happen, just a matter of some alien getting lost, or over-curious I guess. But until that happens all science has to work with are essentially ghost stories. The idea that science is close-minded on this subject demonstrates a lack of understanding of what science is about. The bar isn't as high as UFO cultists claim.
Edited to add: Those places are test-ranges in California, Nevada, Utah, Arizona, and New Mexico where missiles, and ECM are put through their paces.