They do. But then if you want to go into an alite unit (80% washout rate here) with the extra long and expensive training, they want more. Most Seals stay in for the whole 20 years.
Not according to series write ups. The Duttons are Sadistic, murderous assholes, and how anyone raised that way could possibly pass the rigorous psych profile they get is a big stretch. I watched two epi of 1923, and it led with them torturing and murdering 4 innocent sheepherders- and getting away with it- legally anyway. And stealing their sheep.
Note that Yellowstone ends in 2023, with Kayce-
So in 2-3 years, Dutton finished his Navy Enlistment, Seals training and seals deployment?