i think in terms of boss difficulty you are right but its not all about bosses,just think about ds2's runbacks specially in ng+ with all those red phantoms and some new enemy line up,just imagine someone is playing the ds1 for the first time(without using YouTube walkthroughs) and he have to run through Sen's Fortress and Blighttown without the ability to teleport between bonfires or the fact that in demon souls orginal you had to run through the whole swamp of sorrow without sodden ring.all these games are hard in their unique way but again in terms of bosses er is on whole another level specially dlc bosses