I think this is an excellent solution but I also think that the donor should have to update medical issues they may have over the years..
Really if you do not want to deal with a possible off spring then maybe you should simply not donate.
And this will probably be the decision made by most prospective donators thereby throwing future hopes for donated sperm into hopelessness. i think the program will eventually be ended when donators are appraised their anonymity is not guaranteed.
medical science will have to come up with something else to help those unable to procreate without donation help.