Bot teams do appear to have active changes to game shape. Since they usually don't use every player on their roster, players who don't play appear to settle into mediocre GS, while most regular players are proficient or strong. Since they don't play scrimmages, there is little risk of overuse, unless they have a good cup run.
This might demonstrate that they are training GS, since I have injured players below mediocre GS. That is, a player who never ever plays, but continually trains GS may be able to maintain mediocre GS.
After having looked at a true bot, the lineup setting must be more complex. They do use their draft picks. So they aren't locked into permanent rosters. And they appear to make adjustments for injuries, since more than 12 players have games this season. But the extras have very few games - as if they were brought in only when others were injured.
There are currently no injured players, and the lineup for their last game did include the 12 highest salaried players/
But the highest salaried player did not start at the 1 position - but the 2nd through 5th highest salaries did start in the 2 through 5 positions. The 6th highest salary started at the PG. The highest salary player is a C. So perhaps salary is just used as a first pass, and then adjustments can be made based on skills for a position.