Folded ribbon tweeters I’ve heard in recent years delivered a very relaxed and non fatiguing sound, almost to a fault if one expects recordings to have a bit of an edge to it from time to time.
Which folded ribbons are these?
I lived with Dynaudio speakers with the superb Esotar2 tweeter for eleven years. After I sold them and bought a much less expensive pair of ADAM Audio ARTist 5 active monitors to tide me over, I was surprised to find that ADAM's folded ribbon tweeter was even more lifelike, present, and revealing than the Esotar2. Certainly no lack of bite there. It's hard to tell how much of the improvement comes from the tweeter itself and how much from the removal of the passive crossover between amp and driver.
Note that "folded ribbons" are actually air motion transformers, a completely different technology from ribbon drivers.