I'm getting similar problems with the new KeyCaptcha system. A lot of times they solve, but the page isn't accessible, and a refresh is needed to re-solve the puzzle, sometimes it works, but most of the times, it doesn't. I've successfully solved a dozen puzzles in a row (when you get the green checkmark) and it won't load the page. Hitting the Submit button repeatedly does nothing. I also tried a different page/post, and got stuck there too, so trying a different page/post doesn't help either.
At least hCaptcha worked normally (for me). I hope that whatever captcha system ends up being used, will work like it's supposed to. Otherwise, (some) people might not be able to access the site contents as easily anymore.
Basically the captchas are presented because the site thinks we're bots. But if humans cannot access the site, then I'm not sure if they're going to help that much. Maybe I'll just have to try back later (or tomorrow) and maybe it will start working properly again. Maybe not a lot of other people are having difficulties getting past these new captchas?
EDIT: For now, it might just mean trying back later. After getting stuck for a while, I tried yet again, then it worked. Then I got stuck for a long time again... I didn't have these kinds of page-load problems with hCaptcha.