It is advantageous for several purposes, mainly remote live view and remote trigger.

For example:

• Taking photographs on a tripod: usually when shooting far away objects with long exposure you use the 10-sec selfie timer to give the tripod+camera vibrations some time to die out, but when taking photographs of fireworks they happen instantaneously at a moment's notice so you cannot photograph fireworks with a 10-sec selfie timer and the only possibility is remote shutter release if you don't want to upset the balance of a tripod
• Taking selfies in a more professional way than holding the camera at the end of a selfie stick or facing a mirror

There may be also some benefit in transferring the pictures wirelessly without having to remove the card from the camera.

I wouldn't buy a professional DSLR / mirrorless camera without Wi-Fi and the possibility to remotely trigger it from a smartphone. Some other remote trigger than smartphone could be a possibility, but they are just ... old-fashioned.

But if your daughter isn't planning to use a tripod, then the Wi-Fi could be something she doesn't need. I see Wi-Fi and tripod heavily related: you need both or neither.