it's pretty sad that when i was still in BCT, to even complete week 4, you had to had 23/40 at 50 through 300 meters or you failed, had remedial and if you kept failing you would be separated from service. most people (from my own memory, so maybe i'm wrong or we were an outlier) were in the 30+ range. people that had 35 or better could try the 800 meter targets. i still remember my score of 40/40 and 38/40 earning me a sharpshooter badge at Campbell's 800 meter range with an old M16A1E1. good times.
i figured that the rumors of just allowing qualifications on red dots were exactly that - rumors, and you would get training on them together with normal training with iron sights. that's how it was in the 80's through the 90's and into the 2000's. basic marksmanship fundamentals was required for mastering the very expensive, and you're responsible for buying the batteries for, electro-optics.
edit: also completing BCT isn't the end of rifleman training. combat arms goes to schools for specialty training on top of it, regular qualification if their job is specific and has new gear or doctrine, and multiple field exercises per year, not to include combined arms training or integration and familiarization training which also happen often enough - typically before deployments.
i had far less frequent training during my law enforcement career than my time in the military purely due to cost concerns and a bigger focus on the law and community aspects of the job vs when my job was primarily to be pointed at things and told to make them go away permanently.