It is so not useful that I shall not even deign to name it.

You mean a selfie stick?

"That modern object is not useful" seems like an awkward and unnatural use of "object" to me.

Duo didn't accept thing instead of object :-o

They mean fidget spinners?

why not "uze" ? ahehehe please dont hate

Sounds like something you would say about x-rays, vaccines, planes, and rocketships... this is as weird as that "American youth don't use stairs" question in an earlier unit...

Kaj ĉi tiu frazo ne estas utila, avino.

tiu or tio ?

Ne estas sounds like nes ta, blurred together

Pff... Modern stuff.

I did not get a sound through so had to guess the words.