I started my career in Web development using PHP. Since that day, PHP was evolving and getting more robust and performant than before. With Frameworks like Laravel, PHP has increased its popularity, keeping it one of the main programming languages that companies choose to create their websites.
Many reasons make me move from my comfort zone to challenge myself with a new programming language.
This combination makes you to master two different programming languages and switches the way you write code from one to another.
In the end, most of the time is spent on the user interface and less on the backend. The hard work is now on the frontend.
The first reason for moving to Node.JS is to utilize the same language both on the frontend and backend. And this leads to the next point.
One common programming language allows having more synergy between your team.
Now all the team can switch between projects and collaborate with other members.
There is no more, the backend guy or the just frontend guy. Of course, all of us have our strengths and weaknesses, but It doesn't block to support other members with problems or deadlines.
Because all the team members use the same languages, They can review each other code allowing them to strengthen the team.
In the PHP world, some libraries depend on a specific version of PHP, but in the Node.JS world, everything is compiled at the end with the help of webpack, etc., so you don't need to worry so much about these problems.
Same as PHP with composer packages, there are NPM with millions of packages to help you to create sophisticated websites.
Because your app mostly depends on Node.JS that comes by default in most of the OS. It's effortless to host your application anywhere.
Node.JS/JS apps are the best fit for serverless solutions, saving you cost, and ensuring that your applications scale together with your traffic. You don't have to worry anymore about managing servers.
PHP still an excellent option. I really like PHP; don't misunderstand me. But at the end of the day, Node.JS makes my developer experience(DX) much better, and It's what the market is requiring.