Hi @Masser Not sure I would use the term "old" but obviously the Z Fold 3 and Flip 3 are not the latest updated models. The z Fold 4 for instance offers a slimmer but more durable design using cutting edge technology. see more here https://www.androidpolice.com/samsung-galaxy-z-fold-4-jerryrigeverything-durability-test/ This Fold offers better performance ,improved battery life and enhanced camera. With the Flip the new model is faster with s8imilar improvements with Battery and Camera. However for anyone with the previous devices already depends on their needs if it would be worthwhile upgrading, a lot of the changes incremental.
I wouldn't say old is the correct term for it. Just not the newest device. It will do everything that the Z Fold 4 basically does. It's still going to get all the software updates In fact Samsung still lists them available for sale on thier website. So it's still a current phone. I enjoyed using mine, just I preferred the specs of the Z Fold 4 with the wider front screen
