I recently got the Huawei Mate 20 Pro for similar reasons as yourself. The results are extremely good for a smartphone. On closer examination the image quality does not match that of my Olympus EM10 MK2, EM1 MK2 and Canon 5D MK3, which is to be expected. Also it gives me a some comfort considering the investment I've made in "real" camera equipment. ;)
But for a smartphone camera it really is very good indeed, great for record shots and with good light, good enough for most everything else. In night mode I've found artefacts, softness, loss of detail and over sharpening are obvious on a larger screen. I've used the Pro mode and successfully imported RAW images into Lightroom, so great scope for improvement through editing. Low light in pro mode does add a lot of noise.
I've bought a tripod grip for the phone, and will take it for a spin and see how well it handles night shots in night mode and Pro mode RAW. I'll pop up an article on my blog about it when I'm done.
Thank you for sharing your opinion. I completely agree with it.
Of course, this thing will not replace even an amateur SLR camera. But will allow to quench the thirst of the photographer, when the camera is not around. 8))