For me, being stuck at ‘Subscribe Pending’ does seem to happen for KBIN mags, but it isn’t exclusive to them. Whenever it happens, it does the mad thing of bringing everything though up to the point I tried to subscribe, but nothing after.

To fix it, you can often - but not always - go to the source Mag or Community, and find a semi-recent post from after you subscribed, and copy the absolute link (e.g. https://kbin.social/m/science/t/383186/Visualizing-the-mysterious-dance-Quantum-entanglement-of-photons-captured-in), then go to your instance and post that in the Search field. And then the change the thing your searching for from ‘Communities’ to ‘Posts’, and then wait a bit, and then click the link if it shows up.

This tends to force through the change past ‘Pending’, and from then things will start turning up.

If your instance was set up a while ago and nginx was used the config might need updating because the old config wasn’t compatible with kbin. After that it worked well for me. The only thing I notice is that old posts are not synced after subscribing. Only new posts get added.

Also, for whatever reason I actually do have ONE single post originating from kbin, from 3 months ago:
https://lemmy.megumin.org/post/128103

I’m guessing this is the first one I tried subscribing to… so for whatever reason I managed to receive that one post, but then no subsequent posts, comments, or votes.

All of my Lemmy subscriptions seem to be working fine.

Personally I don’t have any problems with subscribing to kbin magazines. The only issue there is is that sometimes federation is a bit brocken and some posts appear a lot later on lemmy, and in rare cases they don’t even appear.