it´s kind of a helicopter drop for all bitcoin hodlers. The new coin has the same history as the original bitcoin but has more "space in the blockchain" for transactions. So the transactions should be faster and cheaper. The main reason for the split is the fact that segwit did something against the scaling problem, but there are miners which have mining racks with asic boosts which can´t be used with the originial bitcoin anymore. So this miners would´ve bought this new stuff for millions of dollars and now it would be worthless with segwit.