Not really. I have two other original models on our 2nd large geo HP that are still running fine. And back in the 80's I installed a couple Grundfos on a new boiler I put in our Randolph house. That's still going. They're a lot like Gould inground well pumps. Running for 30 years is not uncommon at all. But of course, nothing lasts forever.
The other thing I like about the Grundfos is that they use the water for internal lubrication. They don't depend on oil, grease etc.
1st rule of auto preparedness is, don't travel if you don't have to.
2nd rule of auto preparedness is, pay attention to the damn weather before you travel.
3rd rule of auto preparedness is, make sure you have at least the basics to deal with the projected inclement weather, that you've decided you need to travel in.
and that would of been my fourth suggestion. At 28 years, it's surprising it's still spinning. Replacing it would have been number one for me... being without heat isn't fun.
If the impeller spun OK, my guess would be dead spot on the windings.
Well, if the ratings on the old cap and the new cap on the new pump are close, you could do a quick swap of them and test the old one, to see if it starts the new motor.