What it really comes down to is all these streaming services charges the same 10$ per month. Google music gives u the best bang for your buck because with that same 10 you also get youtube red(ad free youtube and the ability to listen to videos while your screen is off on mobile and being able to download videos directly to mobile and watch them offline)
Google music also lets you upload your own music and it instantly syncs across all devices. So the small number of releases that are apple/tidal exclusive just grab that zippy and upload it yourself!!
Google music also syncs up with google voice for voice recognition
Once that soundcloud integration hits google music it's a wrap

You can already save soundcloud tracks directly to your google drive.