Building smart objects and previews freeze the computer!

Building smart objects and previews freeze the computer(Mac mini m1). It is logging so much during the process, so it's very hard to use any other apps. It is lagging so much, so it's even hard to move from one screen to another screen.

I talked with Adobe technical support. They suggest me not use any other apps during Lightroom building smart objects and previews. They told me that's how it works, which is nonsense. I am a wedding photographer I import thousands of thousands of photos a month. It usually takes a couple of hours to build smart objects and previews.

Do you guys any solutions how to prevent lights from using all the CPUs power?