There is definitely some performance difference with VEP7 compared to VEP6 on the mac. VEP7 is improved substantially, but only if you are on Mojave (or possibly High Sierra). When I first upgraded to VEP7 I was on Sierra and performance was worse then VEP6. I complained about it on the internet and ended up working closely with Martin at VSL to figure it out. We both ran tests on our systems and he even made some improvements to VEP7 that made it even faster, but in the end, we decided that I needed to upgrade to Mojave and when I did VEP7 out performed VEP6. The difference was particularly noted when the GUI was open (as opposed to being minimized), so the difference was not related to DSP, it was more related to OSX and graphics, etc.. It seems that VEP7 makes use of Metal and stuff that you need to be on Mojave to take advantage of, and if you aren't its a little slower. This is primarily related to a third party GUI development library that VEP is using, which has added performance improvements that take advantage of OSX Mojave, unfortunately at the expense of being a little more sluggish on older OSX. Its not a big difference, but a little bit yes.
I should add also that my system is using HiDPI on the monitor (ie, Retina display) which may have also contributed to the results in some way.