This is pure bullshit. Yes a DSLR is big/heavy and you have to make some effort to carry it arround. Bottom line is if you don't even want to do that, you are not going to make the necessary effort to get a great picture. You are not going to move to get a better composition, you are not going to want to take the right apperture or shutter speed and you are not going to wait until tourists are gone to take this shoot or go back to place when the lighting is more interresting.
Getting a DSLR when you come from a smarphone/compact is the easiest way to get noticably better shoots. No amount of learning with your smartphone will allow you to got past the fixed focal, so-so low light performance and almost infinite dof. Even if you don't want to learn a DSLR is cheap, get packet with quite lot of quality. Just try and shot and you get something noticably better than with a PS.
On the contrary with a PS you need all the knowledge to bypass all the limitations of the gear and still get great results.
Here my first shoots on flickr after I got my DSLR to get better pictures... Many issues, far from perfect... Still noticably better than what I got from a PS or smartphone: