In short, if your parties DPS is really bad, yes. This question always depends on the math of the parties DPS. For example if grab mastery + items gives you 10 percent more bonus damage, you need to compare that 10 percent to your own damage increase. If that 10 percent bonus damage to each of these DPS adds more than you would gain by equipping DPS gear, then you should be stay support. It's hard to measure this since dps in dfo is so situational and if you're focusing on necksnap/max fling duration holding your party will probably just benefit from more support.