In the last two years I have owned systemsix ( aero road bike ), alloy topstone ( gravel bike ), giant revolt adv 2 ( gravel bike ) & now Ibix MX gravel bike.

When I put on the same carbon wheels with the gp5000 tires the SystemSix is a tad faster if I am trying real hard to go fast. I have a 37 mile loop that once in a while I try to avg 20 mph. At my lower power lever and speed seems like the aero bike was good for about 0.5 mph maybe 1mph that would be stretch. 1 mph is a lot if you are trying to go fast on bikes. A more powerful rider at higher speeds would notice a bigger difference in speeds.

If you like to ride in an aero position at 95% of the time at 95% of your power on your bike rides get the faster aero bike. You will enjoy it, they are fast!!! The person riding the bike is the biggest aero draw back. So if you not in an aero position your aero bike is not doing much for you.
Since 99% of the time I am not in an aero position I found the comfort and versatility of a gravel bike with multiply wheel sets suites me better.

The rest of time ( group rides, fitness rides, stop lights etc... ) there is zero difference in speed.