Solved
Page model.json doesn't fetch the template nodes (responsivegrid)
I have a React SPA page where the homepage.model.json fetches components authored in the template under structure -> responsivegrid -> component A, component B. This expected functionality is not working on a specific page, where the responsivegrid node itself is not fetched at all. There are 4 responsivegrid nodes, each containing some components. The page was working fine earlier, and this issue seems to have started recently (perhaps about a month ago). I'm using AEM 6.5.22. Interestingly, I can see those nodes when the page loads the en.model.json. I’ve checked the template policies, error logs, browser console logs, restarted the org.apache.sling.models.impl bundle, and even restarted the instance—but none of these helped. Also, I couldn't reproduce the issue in my local or other instances. Please let me know if anyone has any idea about this issue.