This is an arguable question....both sides have points.

Break up the roots as gingerly as needed so as to NOT dissturb them.

In other words, the less you touch them the better.

But do what you must to get them out of the pot they are in.

Just make sure that the medium you put them into is NOT compacted.

This will allow the roots to mov freely into the new medium whether you disturbed the roots or not.

But the rule is, generally, just loosely drop the medium into your container, then carefully place the plant in there, then gently fill in the sides...WITHOUT compressing.

Water immediately and let the water do the packing. After a day or so, then you may compress the soil.....lightly.