golfyankeesierra
Seriously. What are you talking about. In the Uk 80 - 90 % of railways signalling has been replaced by LED. No dim signals. Consistently bright illumination of correct colour lights that last for year after year. And (not no 1 priority - but important nonetheless) low energy money saving lighting.
Railway signals are not runway lighting - but common - they suck?
If you are saying they do not perform adequately on landing then that is a lens issue rather than the lights themselves.