I'm actually curious as to how "purist" is being used in this context. I consider myself a purist in that I prefer to watch the original series with the original effects and the NBC broadcast sound mix (or - at the very least - the 1980's - 1999 sound mix). No alterations to make the episodes work best on an HDZTV or 7.1 surround sound home theater set up. As it was shot and made for first run airing.
So the term doesn't mean anything to me in this particular context.
I don't know how the original poster defines the concept of a TOS "purist," but my conception of one is someone for whom nothing that contradicts the third revision of the Star Trek Writer's Guide (Old Testament Star Trek, if you will) counts as "real" Star Trek. By that token, Star Trek V isn't "real" Star Trek because of Sybok's existence as Spock's half-brother. TOS Spock has no siblings, half or otherwise.
Spock-Prime comes from a "New Testament" reality in which Star Trek V occurred and in which Spock has half and foster siblings.
So, for a certain flavor of Trek purist and school of canon-fundamentalism, the inclusion of this image of the cast portrait from Star Trek V in the "Kelvin heresy" could be seen as a loving tribute to actor Leonard Nimoy and to New Testament "Prime Timeline" Trek while leaving Old Testament TOS untouched.
Now, as to the question of "How many Burnhams can dance on the head of a pin?" and "What does God need with a starship?" . . . . the High Church of the Great Bird is silent and the Fontana of Wisdom is, unfortunately, unreachable.
Right now, a voice is singing in my ear, "It's just a show, I should really just relax."
Confession: I actually do like a good bit of Star Trek V and don't consider it the travesty of its pop-culture reputation suggests, and Beyond is my favorite Kelvin Timeline film. I also like Discovery and am looking forward to SNW.