One data point: a good friend of mine joined [large rdbms vendor] out of college about 25 years ago and rose through the ranks in the rdbms engine group. He's now one of the senior people who knows where all the bodies are buried in the code, the forgotten bugs that resulted in the current weird algorithm in the xyz module, etc. I have no idea what he makes, but when I tried to hire him during the first internet bubble they slapped the golden handcuffs on him. These days he's rich from 25 years of stock options.
Your comp definitely plateaus if you remain an individual contributor. You become more valuable, and more highly compensated, by managing and/or mentoring people, helping evolve the technology to match the needs of the business and to find new markets, touching customers and revenue, etc. In my opinion this is required from all senior level technical people in the software industry.