Is element on the main profile or are you waiting for notifications from secondary profiles? Also, might not be related, but my messaging notifications w/ GrapheneOS has gotten worse in the past week or so (Google Messaging hasn’t always alerted to new messages until I open the app and it pulls them) so it might be a Graphene thing as well.
I use the bluesky bridge. One of the issues is that it is opt-in instead of opt out. I feel like most of the people I find that are using the bridge are likely also part of the federated universe to begin w/.