Use Parts From Symfony, Laravel etc

I gotcha so pretty much exactly what Taylor did with CodeIgniter to create Laravel 3. Then later decided using everyone else's core components would be better in Laravel 4 and yet again makes name spacing changes in Laravel 5.

I suppose if every PHP framework followed the PHP PSR's there would really be no advantage to choosing X over Y because, at that point they would all be pretty much the same.

What advantage would there be to use CodeIgniter at that point over Laravel?

If we are able to make CI faster and simpler than the other frameworks it will have those important advantages.

Its normal that CI has to be updated with the "current" PHP standards which are including different things. 
Using some PSR which is already in use from another framework has nothing to do with those 2 framework advantages ..

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