iOS supports this with "Guided Access" mode. It has to be enabled in settings, then a triple click will turn it off/on. It can have its own passcode as well. I use it when handing my phone to my kids--start a video, enable guided access, and not worry about who they might inadvertently call or photo they might delete.
No, it's not like that at all. You have to not just enable it but also select inaccessible areas of the screen. Every time. And they get greyed out which makes it unusable for watching videos while disabling inadvertent interactions (accidental pause/resume/rewind etc).
I'd love to be able to map this to ipad side switch (which no more exists) - my kids use it to fix the picture on screen so that they could put a paper over screen, and use the picture as a template for drawing.
