I have some choices for what channel it could air on.
American Television
Cartoon Network - It would be a good channel, but it doesn’t show good old Cartoon Network shows anymore. It mostly shows Teen Titans Go!, Gumball, or Total Dramarama. The TV ratings are mostly TV-Y7 and TV-PG. There is only one TV-G show: Dexter’s Laboratory. Cartoonito is coming in September 13, 2021. Some shows will be TV-Y. Cartoon Network Will last 6 hours now.
Nickelodeon - This is the best channel to have a Super Mario cartoon. It shows Mario commercials and Kids Choice Awards. This is the only channel that has old Nickelodeon shows. SpongeBob SquarePants was made in May 1st, 1999. It still shows old episodes of It, even season 1 episodes. It also shows 1990s cartoons. Nickelodeon has all TV ratings: TV-Y, TV-Y7, TV-G, and TV-PG. Nickelodeon is my favorite channel because of old cartoons like SpongeBob.
Disney Channel - Disney movies would be made in Illumination, Dreamworks, or Universal Studios. Some movies are in 3D, and some movies are in 2D. The TV rating is mostly TV-G. Disney Channel mostly shows live-action tv series.
Disney XD - It would show Anime shows. It is the same as Disney Channel.
Discovery Family (Hub) - It mostly shows TV-Y cartoons.
Boomerang - It mostly shows old cartoons from the 1940s, 1950s, and 1960s cartoons. Looney Tunes, Tom and Jerry, and Scooby Doo are my favorite cartoon shows.
Netflix - This is my second favorite channel or streaming device to have a Mario cartoon. Video game cartoons mostly have full episodes, and you don’t have to use cable.
Peacock - The Super Mario Movie will come in 2022 on Peacock. This is the perfect time to make a Mario TV series.
HBO Max - It shows TV-PG shows and Cartoon Network exclusive.
Hulu - TV-14 shows are mostly used in this streaming service.
Amazon Prime - It has shows, but it’s an underrated streaming app.
Foreign Channels
Teletoons - This is a perfect Canadian cartoon channel to have a new cartoon.
Let me know on the comments below, and come up with the idea that you have.