Apache is fine. No reason to switch to nginx unless there is something nginx offers that apache doesn't.

In earlier days a lot of people was under the impression that nginx was much faster for PHP, but that was not true. Apache with mod_php was faster, but the issue was memory consumption for non php files as the php module was loaded on every request, even if it wasn't php.

When using php-fpm you don't need the php module on every request as php-fpm is contacted as needed. This does increase latency and decrease performance for php requests, but the difference is indistinguishable for most people.

Slowloris attacks was/is one issue with non event-based webservers.

Both nginx and apache can handle a six digit number of php requests each second on a low end server. You application(Wordpress, Laravel) will without a doubt be a bottleneck before the webserver becomes the bottleneck.