While they don't have any built-in wearout mechanism that's perceptible on a human scale, BJTs can be damaged subtly. This was not recognized until the 80s? 90s? and is even today not all that widely known.
If you reverse-break the base-emitter of a BJT even once, it makes it a bit more noisy. It gets noisier as you go, and eventually the gain starts to drop. Early transistor circuits did not take this into account and often had a big emitter capacitor or similar that could reverse-break the emitter junction at power-off. The accumulation over time can make especially the input transistor of a BJT amp get funky. This is one reason that old effects are often noisy. Well, one more reason.