The problem will be that you could have got grit down in the seals, which will over time rub the anodising off the stanchions, and cause more dirt to enter, rubbing more off, and eventually you end up with a ruined fork.
You wont notice it above the seals, but below they can be a mess.
If you've not serviced them for 3 years, then there is a very high chance they're in a bad state below the seals. So, run them til they die
For me my mantra is:
Regular servicing at home to keep them running
Servicing at LoCo to make them feel brand new
I have no idea what he does differently, but just got my RP23 back from him and it's like a whole new shock. Bike feels so much nicer. I do air can services myself, but it never feels as good as that once a year feeling.