Hi Leo,
I recreated this problem on my own hosting plan with zero plugins except GPP/GB, some fake content, same theme settings, GP elements copied over, and the Infinite Scroll works.
Deducing it is most likely WP Rocket, we may be better contacting their support team.
What are the top 3 cache plugins that cause the most issues for GeneratePress? And do you recommend any alternatives to WP Rocket that create less support ticket?