Of course 'kind' has meaning: mankind, for instance. Or, an illustration Jesus gave: an olive branch doesn't bear figs, but olives.
Even in the pure science, mathematics, there's a whole field dealing with the properties of 'kinds' of numbers: number theory; your argument is akin to saying that because there's only one number 3 there's no such thing as 'integer'.
Sure, there is only one remaining "mankind", human beings, scientifically: homo sapiens sapiens, all of whom can and often do interbreed.
But in the not-so-distant past fossil and bone records show other homo species or sub-species, some of whom apparently did interbreed -- and left the evidence in our genetic inheritances.
So, were they necessarily different "kinds"?
And how many different zebra-kinds are there, or bear-kinds, elephant-kinds, whale-kinds, etc.?
Is "kind" the same as a scientific species, genus or family?
The truth of the matter is, nobody can say for certain, and scientifically, it's irrelevant.
The word "kind" has no meaning in science, and truthfully: no important meaning in theology either.
"Kind" is simply an imprecise word totally acceptable in the ancient world of non-scientific, mostly illiterate farmers & shepherds, but useless scientifically.
OneWingedShark: "your argument is akin to saying that because there's only one number 3 there's no such thing as 'integer'."
Not true.
I have simply challenged you to do the impossible: provide a scientifically useful and relevant definition of the word "kind".