Lower Decks is canon, as are a million other silly things in the trek universe. You’re free to erase all that silly stuff from your personal headcanon, of course, but that means it’s likewise on you to erase upcoming silly stuff from it as well.
Did you see the Strange New Worlds episode where the cartoon character poofed into the SNW universe as a real person, and then another cartoon character came over and then they went back to being cartoon characters? Actual cartoon characters. Not representations of “real” characters.
I saw an episode where canon characters were depicted in two separate mediums, yes. I didn’t see an episode where Boimler became a “real person” because he’s “real” in both shows - they’re just depicted to the viewers in different ways.
This is like saying a novel can’t be canon because a novel is made of ink and paper rather than film.
In the show…an actual cartoon character poofed into SNW universe and became a human (two of them). And then they went back to cartoon universe as cartoons.
It is not like I wrote a cartoon about you but you are a real person. It is like I wrote a cartoon and then they materialized in your room. Big difference.
But Boimler is a cartoon. Then he is not. Then he is again. The show literally embodied a cartoon character and then disembodied them back to a cartoon character.
I get suspending disbelief for sci-fi but that is going a bit far even if it was fun to watch.
Again, it’s fine for that to be your personal headcanon but official canon is decided by Paramount. As far as I’m aware, all movies and television shows (including cartoons and that YA CGI thing) are canon. Novels and video games are another matter.
Boimler is a character, who has been portrayed by a cartoon and live action. Within the Star Trek canon, Boimler is a real character who served on the Cerritos and at some point was transported to the past on the Enterprise.
Then that means cartoon universe is real. Maybe Paramount is fine with that. My personal headcanon is not. I think it is weird Paramount wants cartoon universe to be an actual real universe in the Trek canon. Maybe they do.
If so then all bets are off. They can conjure any nonsense they want to.
ETA: This is different than the Star Trek cartoon with Kirk. While the stories were canon it was just another medium to tell the stories. Cartoon Kirk did not exist as a cartoon that could pop into the “real” Trek universe.
All the previous Treks had their share of humorous and lighter episodes (Tribbles has funny dialogue and comic relief but the plot is about an attempt to poison an entire planet so there are some stakes there for whatever that’s worth) but SNW seems to be turning the light tone up to 11. It also suffers from the modern Trek issue where no one acts like adults. Everyone is written and acts like a teenager which exacerbates things. I like SNW but that is like saying it’s the best song on your favorite band’s worst album.
Animated character popping into to real characters and then going back to animated characters.
It is, literally, making cartoon universe a real place filled with cartoons. Separate and distinct from “normal” Trek universe but every bit as “real.”