Related to #7192, it may make sense to add a config option like autoStart which can be set to false to disable auto-starting the replay.
This would simplify setups where users want to manually control replay recording.

Currently, you can accomplish the same through some other hoops:

replaysSessionSampleRate: 0, 
  replaysOnErrorSampleRate: 0,
  integrations: []
});

// Later when you want to start/stop replay, add the integration
client.addIntegration(new Replay());

However, this becomes tricky when users want to conditionally start/stop replays, as you need to always check if it was added yet etc.