I think no one will argue with the statement that it is vitally important to remember the past. The history of the state you live in is profoundly studied at schools and universities, and the history of your family is not less important either.
How many generations of your family are well-known to you? Have you ever thought about it? I have. Unfortunately, the earliest ancestors I know are my great-great-grandparents, what lies deeper in time remains really vague.
More and more families want to know their background and willingly attend archives to find out the necessary information. Though it is not always possible to restore the family tree due to objective circumstances. A considerable part of archives around the country simply got lost and burnt during World War II. Just imagine that none of your descendants will remember you in a hundred years. It sounds terrifying, but it is our reality. We can only hope that modern data storages are durable enough to keep the memories of the present day.
I have asked my friends the same question many times, and the answer has always been nearly the same. Just assume how nice it would be to visualize the development of your family starting somewhere in the 17th century. I cannot even imagine it. On the one hand the illiteracy of people did them good: if everything that we have at present had been invented 300 years ago, the world would have ceased to exist somewhere in the 19th century. On the other hand this illiteracy made it impossible to collect and store the data about the people who lived in the past. They just lived, without thinking over what would happen in the future.
Of course there are chronicles which have survived through the centuries, but they don’t include any information about ordinary people. Maybe there are exceptions though.
So the more I think of it the clearer it becomes that it is necessary to compile a family tree and write down at least what I know for sure if it is even fragmentary information. I am sure that in the future there will be even online projects of this kind aimed at keeping history of families. I do not think that it is worth while making it accessible to general public, it must be meant only for private use. If such a service ever exists, it will pass the information on to the next generations. And at the same time there must be some paper copy which is a repository of the present and the past. Just imagine how interesting it will be for the descendants to read the chronicles of their family.
I know a woman whose mother is nearly 90 years old, and she made her (really made) write down her reminiscences, everything she remembers about the past, starting with her childhood. And what they finally got was so interesting to study that everyone was surprised!
Summing up, a genealogical tree is not sufficient, if we mean a drawing of it only. It is interesting to see its branches but it is more interesting to get to know some details, including different events that have ever happened. And photos and personal belongings may be a good addition to it.