The best benefit for altitude is to have several thousand years of family heritage at altitude, along with being born at altitude, growing up at altitude and living and training at altitude.
Everything else regarding altitude, one is dealing with Opportunity Costs. Sea level citizens traveling to altitude for several weeks to live and train at altitude has pluses and minuses. Sea level citizens moving to altitude full time has pluses and minuses. Sea level citizens doing high low altitude: living and sleeping at altitude and training at sea level involves risks.
You are stating: born and raised at sea level. Living at sea level. Training at altitude once a week. You are going to deal with pluses and minuses. It is a further stress on the system which will have some benefits. The minus for sea level citizens going to altitude at all is an increased risk of getting sick and an increase of running injuries. Any time at altitude for sea level citizens will increase your risk of injury due to lack of oxygen . I am a sea level person. I have lived at app. 5000 ft. then did a long run once a week at 6000ft. or 7000ft. It is difficult to measure if the once a week to 6000ft. or 7000ft. was a benefit. I went away from city life to run out in county lands. It is common for 5000ft. cities to be surrounded by higher terrain in countryside.