Two things.
1) I do not respect producers dishing out a show that is really handled as if it's a reboot but not having the courage to label it as such. Call a spade a spade. That's called truth in advertising. By not labeling it properly it invites these sorts of debates. It needs proper "mental framing" on the part of the audience. The PR up to this point portrays a show that has a serious identity-crisis as it appears to be all things to all people at once.
2) Just because the look may need to be modernized does not mean that any and all approaches to modernization are good. So people should stop defending Discovery's look soley on the basis of "nobody would accept it if it looked like th 60s". A modernized show does not need Zap Brannigan style outfits or incongruously Steampunk transporter room with misaligned asphalt shingles behind those big radar dish/speakers. That's to say nothing of the Klingons or the Discovery itself. So even if we're totally open to a new look, we're going to still judge it purely on its own merits, and the design leaves much to be desired.
There are plenty of things within Prime canon that a lot of people never liked. The TMP Jammies, the Enterprise D cruise-ship aesthetic, etc... So it's not that purists knee-jerk love anything "canon" and reject any and everything that doesn't copy it perfectly. Some of the production design ideas in Axanar (sorry to say) I think were leaning in the direction of modernizing the TOS look in a way that would probably have done a better job of both fitting into canon and not appearing too-60s. But this idea that the only way to have modernized it is to do everything exactly as we're seeing (including reviving a 1970s rejected ship design that still has a sort of 70s clunky vibe to it) is just incorrect.
Note that
CBS already dissolved its FX team so I think that there's truth to the idea that there's some chaos in their art department and what we're seeing is a direct consequence of that lack of direction / expertise. It's something that looks flashy....but somehow tacky, disjointed, and even sloppy here and there.