We recap, why not re-sist?

I’m asking because I have a Krell KRC-3 preamp on the way. Assuming it was made in the first year of its release (1995) that makes it 21 years old by now. It was recommended to recap the unit, but it got me to wondering about the rest of it.  However, the thought of trying such a feat on a piece of equipment like this scares the bejeezus out of me.

So theoretically, any piece of audio (or other electronics equipment for that matter) has a definite lifespan then, correct? Or is this a case where the caps - because they’re in the signal path - ought to be replaced but everything surrounding them is less critical and can function for decades or longer because it doesn’t affect the audio characteristics?

Just curious about how it all works.

Thanks to all.  My question was first and foremost about the resistors, and that's been answered clearly.  Good info - AGON knocks it out of the park again!

I didn't miss a thing at all.