Pinned knives are nice, for nail jobs. Eventually the pins can stretch and blade play will develop.
I build slip-joints that are completely screwed together. I can take them apart and put them back together as many times as I want. The other advantage I have over makers who pin knives together is that I can adjust the spring after the knife is completed. On more than one occasion I have sent knives to clients who didn't have long or strong fingernails and the spring was too strong for them to open the knife easily. They sent the knife back and I took the knife apart, removed some of the spring material and lightened up the spring action. Screwed the knife back together and put it back in the mail.
To adjust the spring on a pinned together knife you would have to carefully grind down all the pins including the pivot and knock them out. Then remove some spring material, and adjust the spring. Then you would have to pin the knife back together, re-finish the bolsters, and the possibly the scales. It would require you to finish the knife twice. That's a lot of work, and time.
I'll stick with screws,
Chuck