The check frequency isn't the problem, it's the latency between release and update. If a package was released 5 minutes before dependabot runs and you still update to it, your lower frequency hasn't really done anything.
EDIT: Github supports this scenario too (as mentioned in the article):
https://github.blog/changelog/2025-07-01-dependabot-supports...
https://docs.github.com/en/code-security/dependabot/working-...
The whole premise of the article is that they’re substantially lower, because some time for the ecosystem of dependency scanners and users to detect and report is better than none.