True, but the fins of nanos are way different than the fins of angelfish. Many tetras that will leave "regular" cichlid fins alone are tempted by angelfish fins. Keep a really close eye on them, whatever you add.
Serpaes are another good tetra - probably my favorite. They don’t get as large as the others I mentioned and I noticed no aggression from my group (kept them with puffers and mollies).
As
Deadeye mentioned Columbian Tetras are a good option, I have kept them with acaras and angels before and no issues at all.
Serpaes are good too, they have a reputation for nipping fins but i have never experienced it myself.
Both of these are my go to tetra if i want a school of fish in my tanks, either one would work but personally i would go for the columbians
My experience is similar. I have a group of Colombian tetras, now full grown -2”. Not nippy at all even toward small neons in same tank. In another tank a school of black phantoms; not nippy at all even with angels. In another tank a school of red eyes (M. sanctaephilomena), not nippy at all. It is all on the strength of numbers in the pack.
All that being said, a 57g is not very large, and blue acara do become aggressive. Breeding kribensis can also very opinionated.