I think this is the key thing to remember. The job functions currently performed by the DBA may become more automated, or they may be able to be handled remotely and so outsourced, but someone has to be on hand to install, check for fried connections (or deal with flooded hardware if you live near flood zones), or handle the higher level design functions, etc.

But don't count on all the boomers retiring. If you have read anything other than tech manuals lately you may have heard that people are working longer, deferring retirement, or working part time so they can keep their health benefits (or just keep up with the bills). Among my personal friends we all agree we want to work until we are at least 70, maybe older. None of us can imagine dealing with the boredom of sitting around the house watching (ugh!) daytime TV.