How To Remove Floating icon tray in last upgrade

The “Dock” is a fundamental element of the iPad User Interface - visible at the bottom of all Home Screens - and can be exposed in other Apps by swiping-up from the bottom edge of the screen.

The Dock cannot be disabled.

iPadOS 15 introduces a “Shelf” - used to show alternative instances of the same App. This element of the UI is similarly a core element of the multi-tasking OS and cannot be disabled.

Hello. Are you referring to the new App Library feature for iPadOS 15? If you do not want the App Library to show up on your iPad's dock you can turn it off by going to Settings > Home Screen & Dock > Show App Library in Dock and turning this feature on or off.

There has been a Dock in iOS almost forever.

Why is this such a nuisance to you?

It makes getting at always used apps much easier and faster.

You can organize apps and app folders anyway you find convenient to easily get to in the Dock.

What is not to like?

The Dock has, also, been a part of macOS/MacOS since the year 2000.

Yeah,

That new Shelf feature looks like an issue, but it, also, looks like it could be useful.

I am waiting out upgrading to iPadOS 15 until a few point releases when this get more stable and things work better.

I never rush into any iOS/iPadOS upgrades/update.

I wait to see how all these things pan out with other users with any iOS/iPadOS upgrades/updates.

I ALWAYS choose stability over new cool, “whizbang” features introduced into ANY computer/computing device OS.