Yes! #1 danger of too much spacer stack above the stem - especially with Carbon steerer tubes - is the steerer tube breaking while you’re riding, probably at a high impact moment of your ride, probably sheering off at the stem… and you can imagine then that with your bars and hands no longer attached to the fork the crash won’t be pretty.
The plug piece of the compression plug in carbon steerers (same is true for star nuts with aluminum steerers actually) is meant to sit fully inside the stem clamp area - not above or below it. By being there it provides structure inside the Carbon steerer to prevent it crushing under the stem clamp. So as said above, check the length of your compression plug to make sure it’s placed deep enough. If not, then your steerer’s likely too long for safety.
Another factor: some compression plugs can get fairly long and allow you to pass the test above. But then, if you have say a few CMs of stack above the stem, the top cap has that much more leverage to apply torque at unintended angles to the steerer.
How much stack is good above stem? I’ve seen a lot of fork specs call for 5-10mm. There’s often both a minimum and a maximum. For minimum many manufacturers say not to have 0 because then to get good top cap compression on the headset you’ll necessarily have to have the top of the steerer a few mm below the top of stem clamping area - and that’s not recommended either
For maximum, depending on the compression plug length check, you can probably exceed 10mm if you want to preserve some fit flexibility. But personally I wouldn’t go beyond 15mm for long term.