Maybe yes, the coach is changing my starter, but should it really be that way?
Yes.
As I said, there is another option that does exactly what you expected (not changing the starters), and this is Coach Picks from Depth Chart.
I am very sorry, but I keep totally disagreeing with you. If I am wrong I will humbly apologise, but in order for the coach to do this (not changing the starters), you use "strictly follow depth chart" and not "coach picks from depth chart"...
Well, Strictly Follow Depth Chart will result in minutes being distributed between starters, backups, and reserves (if needed) according to their depth chart assignment and not their skill.
Coach Picks from Depth Chart is somewhere in the middle between the two, so I imagine he will pick the players as assigned in their positions, but might distribute minutes as he sees fits. I expect this not to involve him replacing the starters from the get-go, but then again, I might be wrong.
"I don't know half of you half as well as I should like; and I like less than half of you half as well as you deserve."