That's great, but it's nice to have because it often a good indication of when the thread is getting activity, it's format is perfect on mobile, I can see when users I am speaking with leave me a reaction and no response so I know it was read. It's not a useless feature.
And yes, seeing if people liked an image you posted is useful. Because 99% of people will never respond to a meme image and only react to it. So having some live feed back of an image to see if it is popular or not is useful when you are trying to make content that isn't shit and actually makes people laugh. And doing it quickly is important.