Sorry, PHP was not made to build computer programs or operating systems, in the first place, it was not done with the same focus of Net Core that allows the creation of multiplatform applications, and Net Core is not necessarily something dependent on a web browser to serve the content, unless the application is facing the web, then the comparison is cowardly. PHP does a great job on the server side, can be used on Linux or Windows servers, has a great community, formidable documentation, you learn, create, debug and solve application problems very quickly, you can create sockets for you to communicate with your php application, nothing prevents you from creating an Android or Windows application that uses a php application API / socket.
The php is powerful, you just need to know how to use it, have clear objectives, it is not a mere weak typing language as you suggest, in addition, the low performance in laravel is typical of any framework, the problem is that it passes for dozens of files, make several requests, not only serve the content, have checks to be done, one of them is to validate the csrf tokem, this is hell for a server, he is dealing with several clients, he is taking risks, and every requisition he is forced to process a flood of information, this is not a particular php problem, facebook created ReactJS and started using ajax to modify the content, their tactic is to decrease the number of requisitions and this is the way, the server needs breath, otherwise it reduces performance until it actually dies.
If the performance of the laravel bothers you, it is appropriate that you build your own framework, but make no mistake! Contrary to what you say, php is for professionals, I challenge a layman in php and composer to create a framework like Laravel, this is not an easy task, it takes many months and many hours of study, you need to know about php, about the server, about the http protocol, you need to create self-defense mechanisms against client-side attacks, php handles this very well, its focus is on the web, it has nothing to do with Net Core, if you want to install things the path is a PWA application, modern developers only opt for languages like assembly, C# and c ++ when this is really necessary. PWA is the future, nobody needs Net Core or multiplatform language, to do something really good.