Depends on the manufacturer, on a lot of phones getting root access is not that difficult. The problem is that a lot of applications started to check for root access and will refuse to work if they detect it. So in practice you will loose some functionality that can be important, like your bank application.

It's not just individual bank apps. Netflix, Snapchat, Android Pay, Pokemon Go, and Super Mario Run will all refuse to run if they detect root or any other modifications.

So apart from banking nothing of value was lost

My local bank removed a bunch of these checks from their application, presumably because they started requiring everyone use that app for 2FA now and promptly had their support lines overloaded by customers no longer being able to do any banking.

I was one of those people threatening to either walk or get another option - lo and behold they signed me up for the old 2FA for a few extra weeks.

I don't know what they were thinking, really. Rooted phones, or in my case, custom ROMs like LineageOS are quite common in these parts.

My bank is just one of many using a reskinned version of the same 2FA app, so you might want to re-check yours.