If the Chiefs release Smith early next year, it won't be to add offensive free agents. For one, they tried that with Bowe and Maclin, giving identical 5 year, $55 million dollar deals that blew up in their face.
#2, the list of free agent wide receivers is pretty much dogshit. I doubt the Dolphins allow Jarvis Landry to leave, same with the Texans and DeAndre Hopkins. Alshon Jeffery will be 28 and he's injury prone. Maybe they might be able to lure Allen Robinson but it's likely that the Jags will at least use the Transition Tag on him, so he'll cost at least a #2 and $6 million per.
The rest are a whole lot of "meh".
http://www.spotrac.com/nfl/free-agen...wide-receiver/
The Tight End market is pretty weak as well. They're already paying Kelce $9 million per, so they're not going to get into a bidding war and pay Tyler Eifert $10 million per or more (and Cincy is likely to keep him). If Escobar or Travis plays well, both will be on the cheap (and Travis will be under contract next year, anyway).
Again, the rest are a whole lot of "meh" and none deserve big contracts.
http://www.spotrac.com/nfl/free-agents/2018/tight-end/
They're going to save a ton of cap room after releasing DJ, Hali, Reid, Harris, etc. and unless Mahomes plays like Dak and/or Smith takes a gigantic step back, I don't see the Chiefs rushing to clear cap space by releasing Smith with the reasoning of getting more weapons for Mahomes.
They'll continue to do that in the draft.