The top of the lid will be supporting your gear and that's a good thing.
Let's take a look at the camear gear and setup has with ATHLETE PACK: Super Shallow
Just to make sure I am clear >> In the Athlete Pack you can expect gear to sit above the height of the dividers and sidewalls. This is expected and normal. It's a super shallow pack!
You will find that when the pack is zippered close there is a lot more room inside than one can measure with a ruler. In terms of usage, you can expect tall (6in / 15cm) sized gear to fit. It's important to note that tall gear should be arranged so that there are no highs and lows.
If you do not balance out your setup, your backpanel will have a dip. When balanced out correctly, the backpanel is designed to secure your gear. The fit will feel firm and secure and flush against your back.