In the presentation 'Turbo Boosting Real-world Applications' at RailsConf 2018, Akira Matsuda discusses optimizing performance in large, legacy Rails applications. The focus lies not only on application code but also on the Rails framework itself. The key points covered include:

• Performance Bottlenecks: As applications grow, performance issues arise, often due to blocking operations and inefficient component interactions.
• Non-blocking Operations: Matsuda emphasizes the significance of making API calls and database queries non-blocking to reduce waiting times, highlighting a 'future pattern' approach by utilizing threads to handle operations in the background.
• Optimizing Database Queries: He introduces strategies to improve database interaction by sharing connections across threads and using connection pools effectively.
• Action Views: He addresses the performance of rendering partial templates, advocating for using concurrent rendering to reduce wait times in view processing.
• Lazy Attributes: The presentation emphasizes tweaking attribute accessors in Active Record to improve response times significantly by minimizing method call overhead.
• Named URLs: The speaker identifies named URLs as a performance drain and suggests caching mechanisms as a solution.

Matsuda supports his technical points with practical examples from his experience and explorations within the Rails framework, detailing potential optimizations and sharing code snippets on GitHub for further exploration. His main takeaways stress the importance of identifying slow components within the framework, the complexity of thread programming, and the necessity of proactive performance hacking. He concludes with an encouragement to embrace these performance improvements in production environments and the future development of Rails frameworks.