In a similar vein as the mast question asked a little while ago.
I did upgrade my boom from my carbon slim RRD boom to a Liberty Wave boom. I've got golfer's elbow, and the Liberty (25mm) made it worse. So I've gone back to my RRD (24.5mm) boom.
When do you change your boom?

Decrepit, just the fella I was hoping would answer. I was kinda shocked when you said you have masts from 30 years back. I've taken masts off the upgrade list now.
I have a boom graveyard here: a few aluminium and two carbon, one broke at the head, and the other broke where my harness lines were. Nobody wants to get caught out the back or in the break area with a broken boom, but that can happen to new or old booms from being rumbled in the surf.
A bit of a how long is a piece of string question, but does carbon have a usable lifespan?

Carbon doesn't like point impacts, that can break the highest loaded fibers, this may not be immediately obvious, but can lead to a complete break down under load.
UV can also damage the surface epoxy, you'll see old stuff with nasty carbon splinters on the surface. So if you intend to keep stuff a while, don't store in the sun.
My 30 year old masts, no longer look brand new, (as you would expect). But they are no where near end of life.

A break in a carbon tube can be repaired, by removing all the damage, and replacing with a tapered overlay of new carbon. to make sure, the repair is normally thicker than the original tube.
This makes fixing the clue end that slides inside the front half extremely problematic. I'm not game to try this on a boom I want to use.

Aluminum, will bend but straightening it will fatigue it, reducing it's strength.

I wouldn’t straighten a bent alloy boom. The type of alloy used does not like bending back , it will probably break. If it’s only slightly bent , I’d leave it like it is. And even then , wouldn’t use it further than you can swim.

Love how you live on the edge Ollie 🤣! Pushing it to the limits

100% upgrade your boom if it;s flexing of heavy or aluminum… new light, stiff carbon booms are a revelation