Funny how some terms can be diffused enough over time to come to mean almost the opposite of what they originally meant. Continuous Integration is about integrating continuously. "the practice of merging all developer working copies to a shared mainline several times a day." i.e. everyone commits to master multiple times a day.

Then tooling gets built to facilitate this way of working. People start confusing build tooling with CI the practice. Eventually that tooling gets used to support people working in continual isolation on feature branches. People start calling this practice CI even though there's no integration in sight.

Of course true CI isn't applicable for all contexts. Draft pull requests look like a great tool for where CI is impractical.