If you didn't have a need to lock down your radiant electric cooktop, you certainly won't have a need to lock down your induction cooktop (which only transfers power if there's a pan on the hob, even if it's "on", unlike a radiant cooktop, which is either on or its off)

Lots of stuff gets set on top of my induction cooktop - groceries coming in the door primarily. I don't use it as a workspace much, but sure, Styrofoam trays of meat have been set down on it and seasoned many times. I don't use the lock except to keep the kid from turning it on when I'm not home. It's easy enough though - I just press the lock button down, no code to remember, and unlock when ready to use. The only time the error code beeps is if a metal object is left on the cooktop (spoon) or if something spills on top. Mine is a Kenmore Elite, soon to be upgraded to Miele (I hope)!

Can anyone opine regarding this on their 30 inch Miele Induction model 5753? Many thanks!

It's not particular to Miele, or any particular model. If you're actually using it as a work space, rather than just as a place to set stuff down, you should lock the unit so that the controls won't be upset if you cover them up, or have a pool of water, or sense a knife or something and think it was a cooking vessel (which would only matter if you accidentally turned on the element in question). I haven't checked your model's manual for how you enter and exit child lock, but the most common thing is that you hold your finger (or palm if your fingers aren't warm enough) on the power switch for five seconds. Very easy.

You don't want to do anything that will nick the glass, however, because scratches can develop into cracks. It would be worthwhile if you want to use the area on a daily basis to chop on, put potentially scratchy things on (like a cooling rack with metal feet), etc., to have either a cutting board, or maybe a Formica topped piece of Masonite, that fits over the unit when you're using it for counterspace.

If you're just using it for mixing bowls, ingredients, etc., and there's nothing scratchy/nicky or metal involved, and if the controls don't beep at you for being covered, you don't really need to put it in lock mode. I do that all the time on my induction.