How to completely disable the Task View feature in Windows 10?

If you only have 1 virtual desktop, taskview will not be active (default situation). So removing all virtual desktops except for the main one, and hiding the icon is all you need to do.

If you want to disable the overview screen, then go to start -> Settings -> Multitasking.

From the Snap menu, turn off When I snap a window, show what I can snap next to it

Not sure if this will apply to everyones situation but I believe I understand what you're asking.

I tried all the solutions provided in this thread and none of them worked for me.

On my laptop I had to go into the touchpad settings (I've got a Dell) and turned off "Gestures" and the task view no longer appeared when I didn't want it to.