> It's only the subsequent clicks that can be paywalled.

I find it annoying when that happens. Also, Google's recommendation is to allow 5 clicks a day and allow everyone with "GoogleBot" in their useragent. I wish the implementation was better.

> Is it asking to sign in? I tried in incognito mode and I could read the groups just fine.

You are right, I cleared my cookies and I stopped getting the login redirection.