Bachelor's and Master's in CS from MIT. Previously, worked @ Microsoft & Zynga. Currently Co-Founder of Moesif (moesif.com), the most advanced API analytics platform.
NodeJS is definitely more modern framework, with it's non-blocking IO, it is much more easier and fluent to do asynchronous programming. For modern backends, asynchronous and non-blocking IO.is very important.
Php feels like an older technology. It is still very popular, but most people starting new projects/startups probably won't use it anymore (Unless you are really good at it, sometimes it is better to start with a tool you already know best rather than a new tool). Also, Php really allows beginners to easily make security mistakes compared to other techs.
I used both.
NodeJS is definitely more modern framework, with it's non-blocking IO, it is much more easier and fluent to do asynchronous programming. For modern backends, asynchronous and non-blocking IO.is very important.
Php feels like an older technology. It is still very popular, but most people starting new projects/startups probably won't use it anymore (Unless you are really good at it, sometimes it is better to start with a tool you already know best rather than a new tool). Also, Php really allows beginners to easily make security mistakes compared to other techs.
Some data here:
moesif.com/blog/engineering/api-an...
Php just have a lot more attack surface than other frameworks.