depends if the person who sent ethereum has many eth and assets of others in the wallet then I will not return ethereum it to the original owner because he already has a lot of different again if he really did not have any assets in the wallet then I will return ethereum to wallet may he desperately needed money to requirement and eth it could be very useful for him then I will return 100%.
I will do the same thing as you because 1 ETH is worth a lot at this point and the wrong sender will definitely be very worried about that money. I've also come across a lot of cases like this in the past when they sent me 0.08ETH and of course I immediately returned them because the amount was so small. I am not a greedy person to enter this market but I understand how everyone feels about sending the wrong address.