You've been around long enough to know "it depends" 😀

If HyperThreading is left on then I agree with keeping Max Degree of Parallelism below 32 in any conceivable scenario. If you were only considering the 32 physical cores when choosing 16 then great. But if you chose 16 after considering all 64 CPUs then I would drop it to 8.

All stories about enabling and HyperThreading seem to be anecdotal at best. I have seen having it enabled help, hinder and make no impact at all. The only way to know will be to test with your workload.