You may be able to bend a banana a bit but go too far and you’ll be sorry. Same goes for bicycles. All frames flex but it you go to far it won’t spring back. It also means bad news when you roll it into the bike shop as bending is a classic sign of an overload like a crash or other mishap.
With the way bikes are now, light and thin bending is rare. Most of the time instead of bending you’ll get a compression failure and wind up with something that looks like a crushed tin can. Once in a while though the planets can lineup to make something special happen.
