Perhaps it's because I have a spectrum of a sense of humor, but I can see the humor and light-hearted intentions sprinkled and dolloped around the HBO original, Velma. This series has so much controversey around it, so naturally I had to see for myself what exactly was so bad... and I have a different perspective.
Others don't like Velma because right off the bat, we see that Daphne is Asian, Velma is suddenly a person of color, Freddy is seen as a himbo, and Shaggy is not Shaggy, but a very anti-drug black man named Norville - which is of course Shaggy's real name according to Scooby-Doo lore. It's discovered, only an episode or two in, that Daphne was adopted by a lesbian couple and, spoiler alert: Velma and Daphne have hot lesbian tension.
You can see why others may not like it. Blackfacing a Caucasian character really does feel wrong, but that's not what I dislike about it. What I dislike is how Velma is painted as a ditzy, geeky (as opposed to nerdy), and chubby (and therefore unattractive) girl, awkward with mental illnesses - that she ends up using to get Daphne's attention.
So here is what I disliked about Velma:
1) The humor felt forced. The fourth-wall breaking, I'm a huge fan, but when it's done so very in-your-face, like the very beginning when Daphne references the fact that people will freak out over Velma's race... it felt like the writers were holding my hand telling me to get ready to make laugh sounds.
2) Velma was portrayed as a narcissistic little shit, to be honest. She was portrayed as out of shape, lazy, and even upon showing that she has the ability to look attractive, she was given a very unattractive personality. Changing her race to represent more people of color, I don't care. But you changed her entire personality to be some goofy, clueless, psychologically damaged and tormented teenager.
Velma Dinkley is supposed to be a clever, witty girl who, yeah, is a little thicker and curvier, but she never let that weigh anything down, she still wore her signature outfit, and I believe it's also canon that she'd be in sports -- there's no way Velma Dinkley gives off lazy vibes. I don't know, the personality and characteristic changes made it a little less enjoyable.
Now, I will say... going into the series with no prior knowledge of Scooby-Doo, I can see how one would find this funny and meta. The humor of now is a little damaged and I think Velma portrays that for us well. While the characters were not so well written, I do have to admit that it's something I'd watch again, because the humorous parts that were good... were good! The parts that could have used work... coulda used work.
Overall... my verdict is that Velma was fine. It's fine. It's a show and not something to freak about. It's another one of those controversial fads that involves race, so a lot of people are going to be very upset over it for a while, maybe, but the overall truth and fact is, if you don't like the show, don't watch it. It's aired, the mystery was solved, and there's even open opportunity for more mysteries if people like the show enough. If not, no shame in taking it down. Didn't have a cliffhanger anyway.