We replaced Jenkins with Github Actions for all our repositories hosted on Github. GA has two significant benefits for us compared to an external build tool: it's simpler, and it sits at eye level.
Its simplicity and smooth user experience makes it easier for all developers to adopt, giving them more autonomy.
Sitting at eye level means it's completely run and configured right alongside the code, so that it's easier to observe and adjust our builds as we go.
These two benefits have made "the build" less of a system engineer responsibility and more of a developer tool, giving developers more ownership from code to release.