All bitcoins that are not moved for a certain period of time (20, 50, or 100 years) should be presumed lost and then recycled through the usual mining process. I'm not sure if that can be achieved through a soft fork.
FUCK YOU WITH A RUSTY PIPE FOR SUGGESTING SUCH GARBAGE.
but dude it is pretty much certain to get pushed in 2049 to 2069 time range.
and I can tell you human nature it will happen.