Same thing happened in TMP. And no they're not "completely different". They just made the Klingons "more Klingon". These Klingons seem to follow a more ancient philosophy.
That was a change in makeup technology that was given an in-universe explanation with A LOT of backstory. So, all that backstory is ignored?
They seem to follow the basic goose design introduced in TOS. I think Jefferies only designed one Starfleet ship for TOS. I'd like to think in universe there is more than one design. Shenzhou is obviously descended from the NX-Class.
The basic modular design of the ships, in universe, was used across multiple classes. Also, all warp nacelles were cylindrical from Cochrane's first prototypes all the way up until the refit in 2270, including the NX-01. Bridge designs were all fairly similar. Hull shapes followed similar lines. Also, transporter rooms were all pretty similar in layout. Discovery bucks all that.
The Discovery borrows heavily from the design Ralph McQuarrie submitted for TMP that was rejected in favor of Matt Jefferies redesigning based on the original ship. This redesign was, again, modularly used for other ships, like the Reliant and the Saratoga
Now I'm working with only on-screen ships, here. We have the Daedalus class, again with cylindrical nacelles and a very primative shape:
We all know what the NX-01 looked like. Also, a lot of ships from The Starfleet Technical Manual appeared as graphics on screen on the Enterprise in the movies, technically making them canon.
But then we've got the USS Shenzhou with squared off nacelles that sorta look like they're off the Enterprise-E:
And then the Discovery, with rectangular-ish nacelles:
Nope, the other emblems were a production error by the costuming department. Non-Enterprise personnel are seen wearing the delta in "Court Martial". And if we wanna play canon,IIRC it was never called the "warp delta" and all the starbases used the same emblem.
What about the Constellation, Exeter, and Defiant, all Constitution-class ships with different patches? It's not like they were unimportant ships randomly named. They were the Enterprise's sister ships and their patches were shown prominently on screen with significant design work. That letter above came well into production and was seemingly a change in decision
He also has a half brother!!!! And get this, Kirk has a son and Scotty has a nephew!!!! Who knew????? For the record Burnham wasn't adopted by Sarek. She's his ward. Yes there are uniforms.
It's weak storytelling at the very least. How many secret people could Spock possibly have in his life?