Let's look at DPR using the example of my Level 8 monk. Subclass Mercy, Dex 19, Wis 16, grapple feat, relevant magic items are wraps +1 and eldritch claw tattoos (+1; can activate for an additional 1d6 damage/attack once per long rest).
So if they are attacking an apponent that they can grapple (say, a Rakshasa, since she just fought one - AC 17, 221 HP), then her DPR is pretty scary if she wants to go all out. +9 to hit (+4 dex, +2 magic items, +3 proficiency), so a starting 60% hit rate. BUT every round, assuming she hits at least once, the target is automatically grappled unless unless it makes a DC 15 saving throw (Rakshasa will save on a 12+, so assume it will be grappled 55% of the time, giving my monk advantage on attacks). With advantage, that hit rate goes to 86% if my head math is correct, so overall we are looking at roughly a 75% hit rate.
Base damage is 4.5 (fist )+3.5 (tattoo) +4 (dex) +2 items): 14 x 4 (attack+flurry) =56 x .75 = 42, + 8 (hand of harm), or 50 damage per round. Plus the Rak has the poisoned condition the whole time.
TLDR: 5.5e has really increased martial DPR.
Edit: As DM, I'm really struggling with this. For example, that party also has a paladin and barbarian, so at level 8 the three martials alone will typically put out more than 100 damage per round. I'm finding it challenging to create suitably tough encounters for 5.5e. I'm having to completely ignore CR and put in some really heavy hitters against them, so fights tend to be short and really swingy - characters and creatures are going down in 1-2 rounds. It feels like DPR got turned up to 11.
