Never heard of him but I assume he’s good?
His PFF score is 73.5. That means he is above average overall.
I am not sure of all the categories for PFF grades. He has a grade for pass rushing, run defending and tackling. Just to make up a narrative, it's possible he's a 90 in run defense and a 60 in pass rushing. (I don't think so but just to illustrate how the grades work.)
PFF says a 90 + is an elite player. 85-90 is a Pro Bowler. 70-85 is a starter. 60-70 a back up (or situational/ rotational player) At 0-59 you need to replace them.
As I said at 73.5 he's an above average player. He is't all world. As a comparison they have P Smith rated at 66.4, Alexander 72.3 and Clark 79.9 so you can see he's right in the mix. Clowney is 83 but their other 2 DL are right around 60. His replacement was probably about 55-60 as well.