Previews generated - no profit, NC slower than before

I’m on NC22. I installed preview generator. Ran preview:generate-all --path=“myuser/bigphotodir/”

It has been running all night (about 20G of photos in sub folders). It seems finished. Loading a dir with photos in the files app all but crashes the system. Which is the same or worse as before.

What am I doing wrong?

I set first set these sizes
–value=“32 256 2048” previewgenerator squareSizes
–value=“64 256 2048” previewgenerator widthSizes
–value=“64 256 2048” previewgenerator heightSizes

Than ran generate-all as mentioned.