I think Hendricks can/will be a shot blocker in the NBA, but there's a lot of space between being a shot blocker and being the very best shot blocker. He's a good shot blocker, but we don't compare someone his is good with the very best when it comes to any other skill. You wouldn't compared good shooters to Curry, great passers to Jokic etc.
I think Lauri makes more sense. The size+shooting combo is a similarity and I think they will be similar level rim protectors/off ball defenders.....but I also don't love that comparison because Lauri is also probably the best in the league at creating shots around the basket in the half court as a half court player. Hendricks will be great in transition and dunk everything....but I don't see him being close to Lauri's level as an off ball player in the half court. Honestly, I'm struggling to think of anyone who is even close to Lauri in the first place, so this isn't a dig. It's just that Lauri is so unique in this regard. Maybe MPJ?
I think part of the appeal with Hendricks is that he is unique, and thus doesn't have many great comparisons. The size, shooting, and athleticism doesn't come around too often. This is kind of a weird one, but an early comparison I saw was Jeff Green. If Jeff Green started his career in this era and not in the stone ages, I could see it.