According to the “Developer Survey Results 2016”, which was conducted by STACKOVERFLOW, among over fifty thousand developers from all over the world, PHP is more widely used back-end technology compared to Node.js.
In 2015, PHP 7 with new long-expected features was introduced. Possible differences in performance is already not an issue when one compares “Node.js” technology with “PHP” technology.
From the scalability perspective, there are no big differences between PHP and Node.js, it is more important to consider the project’s architecture. https://belitsoft.com/php-development-services/php7-vs-nodejs
In general,it is a good idea not to oppose them, but use them cooperatively.