In short, Renovate (by Mend) is a dependency manager for software projects. It watches your repository for outdated libraries, packages, and frameworks and opens Pull Requests to update them.
There's several benefits we had in mind when building this (after using self-hosted Renovate ourselves):
k8s-native approach: It uses CRDs, so that Renovate configs are Kubernetes resources. You can manage them more easily/granular with Argo/Flux/kubectl as part of existing workflows instead of a Cronjob.
Job isolation: The operator spawns individual jobs per repo instead of one run. If a repo is stuck it doesn't block everything else.
Webhook support: repos get updated immediately, not just on the next cron cycle.
Visibility: There's a light-weight, built-in UI showing repos, job status, and progress.
There's more on the Github repo, we added a full list of features and benefits to the readme.
Of course, in the end it comes down to individual preferences :) Not saying one way is better than the other. We just felt that for us, the operator-based approach would work better and we're happy if the project is benefitial for others as well!