Yeah, regardless of whether you have a road or mtb cassette (with a 10 tooth cog), you are going to be limited by your chainring for top end speed.
What frame do you have and have you tried a larger ring? I’ve done a bunch of gravel racing on my Scott Spark RC and it’s “officially” limited to a 34 front ring, but I run a 36 no problem. Nino runs a 38 on the same frame. Running a 36 in the front and 10-50 in the back, I have never been dropped in a gravel race due to gearing limitations. 34 would probably be fine also. All dependent on course and conditions.