Yes, you can adjust the number of logical processors that MATLAB can use. Edit the cluster profile named "local" https://www.mathworks.com/help/parallel-computing/discover-clusters-and-use-cluster-profiles.html#f5-16540 to change the number of workers to 72 (or however many)
Be warned that when you actually use logical cores, that your Xeon w9 will slow down if the number of tasks in use exceeds the number of physical cores. Your Xeon X9 relies upon micro-naps to cool the processor, and when it does not get those micronaps (because the logical processor use is causing the cores to run flatter out) then your Xeon X9 will reduce the clock speed of the core to the point where the activity fits within the thermal limits. Logical cores are a method for transfering control of a physical core very quickly, so when a physical core would normally be taking a break (such as waiting for a resource) it instead quickly switches to a different task and keeps running quickly. The amount of duplicated resources able to be used by both logical cores at the same time is quite limited -- it isn't literally the case that only one logical core at a time can be running per physical core, but only one at a time can do much computation.
Note that this downgrade to satisfy heat budget requirements is generally not needed on AMD Ryzen systems. AMD Ryzen run the individual cores a little slower, so when the logical cores are running as fast as they can, the total heat budget is not exceeded.
Using logical cores works fine if the tasks involve waiting for resources, such as writing I/O or reading from disks (though there are different reasons why in practice running lots of I/O is mostly not a good thing.) Using logical cores isn't so good for flat out computations: you just split the attention of a single physical core between two tasks but it can only focus on one task at a time, and the overhead of splitting the attention results in a net loss of performance.
