All classes offer DPS. SAM just provides the most by virtue of being the strongest. SAMs won't be dethroned because they don't have any damage raid buffs or defensive utilities to share with the raid. Reapers have a 15 second HoT and a 3% damage increase for 20 seconds.

If you put the jobs on even footing meaning no raid buffs Samurai will always win because of Fugetsu and Fuka giving the SAM a 13% flat DPS increase and a 13% reduced GCD and auto attack delay whereas Reaper only gets a 10% damage increase.

So buff Reaper I guess. It's a low performer among the 5 melee. And because it has raid buffs one of which is reliant on 7 players to empower a PH it's always going to be lower then SAM.

SAM and RPR take the same amount of brain to play. SAM just does more with less. And RPR does less because it has more.

And I'm sure SAM's auto crit helps it out quite a bit. Reaper has to hope it gets all crits on it's burst(it won't lol).