I've been an active participant on stackoverflow.com and meta.stackoverflow.com for a few years now. It's been a while since I've encountered rep-based permission restrictions. How am I supposed to build enough rep on meta.stackexchange.com to effectively participate? Most of my needs are handled on the site-specific meta, so I rarely have a need to actually answer or ask a question here... but I would like to up/downvote on discussion topics.

So, after Martijn's comment, I realize the root of my question is this:

Why, on a meta site where upvotes and downvotes are an integral part of the discourse, am I first given the ability to "agree" and may only later earn the ability to "disagree"?

Which is essentially a duplicate of Why do we have a down vote rep threshold for meta?