Tight ends among all NFL teams are somewhat limited.
You only have a handful of teams, maybe, 5-6 teams at most that have dedicated game plans each game that the tight end gets the ball frequently enough.
It’s very hard to just shift an offensive focus to incorporate the tight ends for every game. Seattle, even when they got Jimmy Graham, was used primarily as a red zone target.
I wouldn’t say Seattle needs to make tight end a top priority cause AJ Barner and Noah Fant is “enough” for a team that wants to clearly run the ball as the main offensive identity.
If you have a Brock Bowers of the Raiders or the Cardinals tight end or La Porta of the Lions, then, you have a solid TE but most teams do not have a league top echelon tight end and they are able to make their offense work just fine.
Seattle’s number one need will always be offensive line….