You're underrating him.
ETA - some more context
I own him in some leagues have been getting offers for him. They are TE premium leagues but can kind of work out value in PPR.
Was offered Ebron and Cohen for him a few days ago. These are two players I tend to be way higher on then most. Credible offer I gave about a minute of consideration before saying no and Ebron in theory cancels out the TE premium factor.
Was offered Lindsdey, Funchess and 2.10 last week. Gave this zero consideration and I while I think Funcess is worthless I think Lindsay is going to continue to rise.
A few days ago I offered Engram for him straight up. Got quick rejected and I asked if I can add something to the offer let me know, they said anything less than a first was not going to do. I might end up doing it.
Before the season started(a few days before Guice got hurt) I offered Guice and a first I picked up which looked like a surefire top 4 pick (ended up 1.1) for Amari and Henry. Key here is the team I offered the trade to only rosters SEC players, has Engram/Reed and at the time what looked like a good prospect in Hurst and RB was their weak spot and I'm sitting on a ton of SEC RBs. If you need RB and only roster SEC players I'm hard to not deal with in this league. Reply I got back was they'd be down to trade Amari, but HH was not available.
Just giving an idea of how some out there see his value. I've been using that Mike Clay top 240 I posted earlier just as a trade value chart(I personally care zero about people's rankings). I think he had HH hovering in 60'ish range, that seems worth the picks to me in PPR.
Also I think his major issue is getting more consistent target usage but keep in mind he's still had to deal with Gates during his first two years and we've not seen him get to remove that obstacle yet to see how he fares. But this time last year I realized he was sitting on exact same amount of targets ,115, as Engram. They were both the same age and people were loving on Engram and I felt he was regarded a little higher then Henry but Henry's production on his 115 targets blew Engram's away. This got me to do a look at where players like Gronk, Kelce and Graham were are in their careers after 115 targets and Henry was every bit as productive as those 3, right on par. And not for noting but Kelce and Graham were as old in their first seasons as Henry is right now, he'll play almost the entire season next year at the age of 24. Which again just means that when he was 21-22, he was as productive on a per target basis as 24-25 year old Kelce and Graham.
I'm only in two PPR leagues so sometimes hard for me to judge value of TE's in that format vs TE premium leagues but what I know is I'd give up that capital for Henry in both of those leagues.