It's hard to tell on a message board.
Carr starting his first two games in comparison to teams having seasoned QBs is a difference. A returning starter is generally one of the things that people consider in their pre season rankings, because it is a difference.
I'm not saying those losses don't count, but it's also one of the reasons that losing early in the season has always meant less than later in the season. Teams change. If you have a new QB, they gain experience and can get better.
I'm actually in agreement with you somewhat in that the schedule didn't really let us know how well they will play against another strong team. Miami's DL whooped the OL, they haven't really played anyone at that level since then, so have they gotten significantly better, or are they able to just block lower level competition? I've still seen receivers running free. Could better QBs take advantage of that, or were those plays missed because of pressure? Can the pressure get there against better OL?
You can certainly acknowledge though that Carr in his first start is different than Carr in his 12th+ start.
Edits: Typos from phone