Imagine being Warren Buffet's age and having his level of success.
Then imagine that some disruptive technology comes along and threatens the empire you built. Are you likely to spend your last decade jumping in and figuring out this new thing while being trolled the entire time or is it just time to sip your Coca-Cola and do the trolling yourself?
I'd like to think I'd jump right in but at his age and station in life, it's hard to know.
This is no different than when Rockefeller was trying to stop electricity to become mainstream since his oil was used to light the lamps and he felt threatened by the potential of this new technology, Warren Buffett has become very powerful under the current rules, so it is completely natural that he wants the status quo to maintain itself and he is going to be against anything that threatens it, when you understand that it is not difficult to understand why he is so opposed against bitcoin and what it represents.