I will note that Intel CPU Mac devices are slightly underpowered for AI processing and will perform slower. We have some more information on our Topaz Labs Documentation page that I will link below for your review:
Many users with Intel MacOS machines have reported that Topaz Photo AI v2.4.2 is most suited for their needs and experiences better processing times and consistent edits and displays. I have included a link to that previous version below if you would like to revert to this version for your machine: