There is nothing in the code that would limit step execution based on log size of prior steps. However, the pipeline does block when uploading the final logs after the step completes, and will retry on failure using a backoff. We have seen people experience similar problems with reverse proxies or load balancers failing large file uploads (due to http request limits) causing the the upload to retry using a backoff until the pipeline eventually times out (skipping remaining steps). This would be consistent with the behavior you described, and can be easily fixed by updating your reverse proxy or load balancer configuration.
Have you enabled trace logging on your runner to see if it provides you with more details of what is happening? Also, have you ensured you are using the latest stable release of the runner to ensure you have all the latest patches and fixes?