My shock is less than $80 (I just purchase new old stock on eBay or eBay auctions. You easily can find new high end past gen stuff for cheap) so it is cheaper just to toss your 1 year old shock in the trash bin or sell it on craigslist for cheap and buy a new shock if you are really so sensitive to feel the difference between the new shock and the 1 year old shock kept clean. My fork is the same, past gen pre high end unit not worth to maintain even every 3 years. This stuff lose value faster than you lose your cash and time on maintenance.
If maintenance would costs less than $15 then maybe it is OK, but even in this case you lost your valuable time for managing it while you can just one click purchase a new shock with delivery to your doorstep faster.
Basically if you can not maintain it within 1-2 hours and it bothers you, just buy a replacement. The newer generation replacement will likely work even better for less price than you spend on your old shock to maintain. But it will likely not even bother you because of if you keep it clean then it will likely work just like new.
People who can not afford professional shop maintenance or a new shock just maintain this stuff themselves and reuse the old components without even purchasing new gaskets and seals just recycling them and do not question if it is necessary to maintain it and how to maintain it.