For a vet min, absolutely. What the hell could it hurt? Dude achieved way more on the field than anybody in the TE room, if any of that vet savvy rubs off on Knox/Sweeney/Hollister, the team improves.
I mean sure, if Ertz happens, might be a different story. But I'm not waiting for the price of peanuts against the cap right now
Full disclosure: Walker probably won me a league or two circa 2017. Quiet, but constant production. If there's no more tread on the tires, move on in August