WOW
this is so unfortunate for him!!
I feel sorry for that guy, but it is old news, unfortunately, as from time to time this very mistake repeats over and over again.
I always check the mempool and transaction fees, and decide correspondingly, is such a newbie mistake!! and we keep seeing people with big money in Bitcoin who still fall in these uninformed behavior.
Because not all people are aware, not all of them are careful before sending bitcoin.
Double checking all the infos or bitcoin addresses is not that easy to do especially if you don't want to put your assets into waste.
Newbies are so excited when they are making transactions with bitcoin because they think that it so easy and fast.
They don't hesitate to check because they are so confident about their accuracy of sending it.