currently curation is linear, doesn't matter when you vote unless you vote after 24h.
Thanks!
if they've been active the last year or so
To determine if an account counts as active or not, I feel only posts and comments should be taken into consideration: upvotes can easily be misleading due to curation trails, which (at least as far as I know) stay active forever (which is something very bad imho, because they can be easily abused if the upvoter stop checking what people are publishing and forget to deactivate the curation trail... but this is a completely different topic! 😅)
Yeah if the abuse becomes excessive there's always downvotes to help deter it.