In the "My WikiTree" menu in the upper right corner, "Family Activity Feed" is a good place to check for edits to profiles on your watchlist, which includes comments left on those profiles.
Next, check "Requests" in the same menu to see if anybody has asked to be added to the Trusted List of profiles you manage. Finally, click on the "Find" menu and then "Pending Merges", and then "Pending Merges Waiting for Action by Me" to see if any merges on your trusted list have been approved.
To see if anybody has responded to your G2G posts, go to
https://www.wikitree.com/g2g/user/Campbell-27846/activity and then click on each of your posts to see the responses. That link can be found at the top of your G2G profile
https://www.wikitree.com/g2g/user/Campbell-27846.
To check activity in your tags, click on "Wiki Genealogy Feed" under "My WikiTree", which will show you profile edits that cross-match with your followed tags. Also click on "G2G Feed" in the same menu for G2G threads with your followed tags. These are usually useless especially if you follow a common surname.
This may be hard to be believe but I truly prefer all of this clicky-clicky over digging through the spam that WikiTree (and every other website!) sends to my email box, over and above the notifications and newsletters I have turned off. At least I know when I click on "Family Activity Feed" that everything on the screen will be relevant and fresh and not marketing spam. And that when I see the update it will be at a time when I am on WikiTree and able to respond thoughtfully.
If WikiTree wants to leverage the social media aspect of genealogy and foster collaboration, the site owners need to do more to support communication between members inside the platform, instead of expecting us to toggle back and forth between email and browser constantly just to keep up with a conversation.