Fair enough, but if the rules don't or can't support those years-decades where nothing is happening it's still a bug.
There's an example in D&D (all editions) of a similar thing that's always annoyed me, and I've mentioned it on the forum numerous times before: what happens to someone's class skills and abilities once they stop adventuring and-or grow old and-or stop pursuing that class? There's no mechanics for it*, and the rules say nothing, thus implying the 80-year old guy hobbling around on a cane is as good a fighter now as he was in his 14th-level prime 50 years ago, which is, in the fiction, ludicrous.
And while one could say this doesn't affect day-to-day play believe me, it does. When I want to make an NPC bartender who used to be a 10th level Fighter but packed in his warrior ways fifteen years ago, I want the game mechanics to tell me what he still has going for him as a Fighter and what he doesn't such that when the PCs pick a fight with him I know how to run him in combat; and I want the game mechanics to do it so I can consistently apply the same things next time.
* - 1e at least had base stats change with age, which is a start, but still doesn't speak to class skills.