Use the camera you want to use, I have the iPhone 11 Pro as my normal phone and is my carry around camera and a Nikon full frame DSLR for my ‘proper’ camera which I used for event photography and if I was going ‘photographing’
If you want / need a good sized sensor and the ability to use ‘real’ lenses then you should get a ‘real’ camera
Many smartphones have really improved the sensors and have good lenses, my iPhone has 3 distinct lenses. Previously if you changed settings for landscapes, people etc the software just changed some settings, with the 3 lenses what really happens is it switches to a totally different lens (and then changes some settings too)
If you’re documenting things then you can just flip out your phone, don’t even need to unlock it and snap away.
My iPhone is great for various types of photos, videos and I also like filming in SloMo
The advantage of using SloMotion mode is I can play about with the finished video, the ‘disadvantages’ are bigger file sizes and if it can’t cope with the lighting.
Advantages of a real camera are that they are easier to hold properly and keep steady and I prefer to look through a view finder rather than at a screen.
Hold a camera up to my eye, using one hand on the camera and one on the lens is a steady set up.
Holding a phone up in one or two hands is less natural and can be unsteady.
However - grab a real camera and people notice, grab your phone camera and you are more likely to get natural results
For quality anything in the last couple of decades can easily get good pictures for on screens or printing.
When you next pass an advertising hoarding with pictures take a closer look - that giant picture is just meant to be viewed from further away, any professional photographers high quality image has been printed at a relatively low quality on big poster paper