[KabaKun]

> You can be a 20k rep Stack Overflow account, but land on a Stack Exchange question from Google and it's a complete crapshoot if you'll even be able to upvote the question.

If you have 200+ rep on any one site, you can upvote on any other site (assuming you didn't spend/lose the rep somehow) if you actually create an account there. Downvotes require more rep (125), so that requires some participation on that specific site.

This Association Bonus (100 free rep on all sites as a reward for earning 200 on one) is designed to address a lot of your concerns. It allows upvoting, flagging and commenting. If you see something that should be closed, you can flag it for closure to bring it to the attention of users with sufficient rep to close or indicate non-answers as such so that higher rep users can vote to delete them.

The system as-is definitely leads to a lot of confusion, though. The explanation I've heard for the siloing of reputation between the sites is that reputation is an indication of trust and expertise in using a specific site. If you know how what's on or off topic on SO, that doesn't necessarily mean you know what's on or off topic on Puzzling or InfoSec. Each site has slightly different cultural expectations, and the belief - which maybe should be tested - is that that expertise doesn't cross between sites.

One part of the problem here is that someone can spend hours using a site and know what's on topic or what should be deleted or downvoted or closed and still never have any reputation on that site... and on the other end of that spectrum, you can find very high rep users who either don't use those moderation tools or use them incorrectly because they haven't actually taken the time to understand how the community expects them to be used.

It's a hazy indicator of expertise at best but it's also a relatively low-effort one to implement. It takes work to balance it and decide what actions warrant a reputation reward but it's okay. Finding a better/different way to achieve this indication of expertise and privilege may be worth considering and may allow users to "test out" in a privilege to earn it without needing a specific amount of points. This would allow invested users access to privileges without requiring them to also be expert askers or answerers.

[pkamb]

> If you have 200+ rep on any one site, you can upvote on any other site

Yeah that's if you create an account there. Land on a random SE site from Google or from the Hot Network questions and chances are you don't even have an account.

The site looks exactly like Stack Overflow, but if I press the upvote button I get an annoying error and the person who wrote that answer doesn't get any points.

If I do create an account, every time I infrequently visit that site I'm met with an annoying banner to "remember to upvote". Despite the fact that I upvote Stack Overflow questions daily. You can't win.

Editing is the other major place where I feel this annoyance. On Stack Overflow I edit a ton of posts to correct typos, grammar, code formatting, and capitalization. But I can't donate my free labor on SuperUser or AskDifferent. I'm not going to add these minor edits to a review queue. So the sites are just worse off because of arbitrary site siloing.

> Each site has slightly different cultural expectations, and the belief - which maybe should be tested - is that that expertise doesn't cross between sites.

I'd very much question that belief. Maybe for the more esoteric sites, but a good user on Stack Overflow is going to be right at home on SuperUser, Ask Different, or any of the myriad slightly-different-but-mostly-the-same tech sites with slightly different focuses.