Kimetsu hasn't even ended and the sales keep growing so how can you measure it's influence already? Its projected yearly sales figures are already mind blowing enough and it's monopolizing the sales rankings on the Oricon charts. Also, you can bet it'll probably win the Tezuka prize. I would be shocked if they didn't give it a full chapter color ending.
We're not expecting a magazine cover send off, which you can argue that's ridiculous (& I would agree) but surely it deserves a full color chapter ending.
It's very easy to realise that Yaiba will not be nearly influential than a manga like Kochikame for example, that was my comparison, will of course be a important series in Jump history because the hard sales, but i find really hard to see Yaiba being a influential series for the next generation of authors or something when taking in count the series as a piece of work.
But my point isn't about deserving or not, i would give a full color chapter for Yaiba and many other big series too, i'm just saying that there are no real "pattern" behind these full color chapters, so saying "it should because it deserves" isn't something that applies for SJ when so many big and influential series never got one, but if it gets, congrats.
