Eh.
I dunno. I think this is a situation where the stats are lying. Or they are inflated by one outlier.
There is really no way you can argue we were better off, or even close to equal, with the TE spot when Witten was here versus last year. The offense as a whole labored a lot more in 2017 vs 2018, which affected the numbers. The security and reliability he offers alone is worth enough to say his production, if it's the same as before, would be an upgrade.
I think people are slightly overreacting to this. Of course if we also draft a TE in the second, that's cool too.