What I like (in limited viewing/knowledge) of Drysdale is his versatility. Sounds like in juniors, he was asked to be an offensive d-man (almost PPG last season) and he was good at it (a consensus top 10 pick). During juniors, he was asked to be a defensive d-man to Byram and up until the finals, that pair was spectacular. Now in San Diego, Drysdale is playing all situations (PK, PP, top pair 5v5) and excelling at that too as a 2-way d-man. I said it about Zegras, and I think Drysdale has this too, both have the mentality that they will not fail. These two are willing to do whatever it takes to be successful at the next level and aren't letting the pressure get to them.
I think what Drysdale ends up being will depend on who he's paired with at the NHL level, give him a good DFD as his partner and he'll open up and be a good OFD. If you need him to babysit a risk taker, he can do that too. Put him with a guy that can play D or push the puck and those two can take turns depending on who has the open ice. The question will be does he end up being a top pair guy or top 4/second pairing guy? He's trending really well, and hopefully becomes the first home grown elite 1D for the Ducks.