Could use a sacrificial board on top of the post. Somethibg that may rot over time but is easier to replace. Also an angle on top is best so the water runs off.

I hope you sealed what’s under the ground. That’s where they usually rot.

I think that's why you're supposed to put a turtle on your fence post to keep the rain off. 😁Seriously though, a lot of folks around here just put a flagstone on top.

these options sound a lot better than painting or staining. I may end up doing a combo of cutting an angle and setting something on top.

As others have already said, angle cut or rock on top. If you prefer some type of sealer, used-oil works well and is cheap.

Could pyrolyze the top thoroughly, Also, hope you did something to the part under ground.

I don't like toxic options, so I personally don't consider it

Iv heard just regular outdoor paint works well. I’m gonna be picking up a can of that flex seal spray paint and just hit all the tops once everything dries out up here