"Plus ça change, plus c'est la même chose"
-- Jean-Baptiste Alphonse Karr
As a member of pmdev, you certainly have the privileges (and the trust) to contribute whatever code you think would help improve the Monastic experience.
Having said that, I'm not entirely sure it's wise to draw a curtain over the accomplishments of those who established the foundations of something that has persisted (relatively unscathed) for longer than many tech careers.
I would suggest that the history (and the library of existing posts) is part of the site's value. (By way of example, perhaps it's worth pointing out that my first post in a dozen years linked to a previously-posted answer.)
I would further suggest that the open culture of (general) encouragement and support for studious effort exists, in great part, because effort of the current Saints.
Perhaps an alternate approach is worth considering. Have you considered something along the lines of a new "Selected Saints in Our Book"? If you model it after Selected Best Nodes, you would be thematically consistent with that feature and could end up striking a fair balance between encouraging new blood while honoring the legacy of those who laid the foundations.
I realize this is (kinda sorta) what you were alluding to, but I thing it's worth spelling out a little more clearly.
I dislike the idea of reworking the vote count/tally/impact calculation, partly because we have (had?) a strong tradition of not rewriting our history. Limiting the roll to a set number of years seems like not respecting our history.
That's my take. Other mileage may vary.
P.S. As I'm sure you're aware, this sort of conversation isn't new. "Omnia illa et ante fiebant omnia illa et rursus fient."