I can see the item limit becoming an issue for sites like blogs with many collaborators.
The 10k item limit is there for performance reasons, but maybe you should add an archive feature that moves older items to a slower system for archival purposes - or even a system that automatically archives dynamic pages like blog posts as static pages?
It is currently possible to Archive collection items either individually or bulk. Here's a related article on University. https://university.webflow.com/lesson/collection-items-overview#bulk-editing-collection-items