Actually, I was going to defend Brobot's feat; I agree that the ones rejected such as the Sunshine paint examples or Yoshi summoning a Power Star by eating a fruit are vague and shouldn't be brought up.
But I relooked at the Brobot example and Weeb brought up good points. First, right as the fight starts, we visually see the screen ripped in half and their's a starry sky background. Some people interpreted it creation, while others see it as merely teleporting to Outerspace. However, when you flip to 3-D, you see Green dimensional lights as if it was some digital creation. It's not the regular outer space seen throughout World 4. Also, upon defeat, the background literally explodes and they just appear to be where they were before the fight. If the first example was just a mere teleportation, Mario and crew would have had to actually fly back to where they were manually and MR L would have had to just been seen floating in space before that. Also, the final part of Chapter 4 was described as a location at the edge of the Universe. But I'm done talking about that feat, but I still think that feat is solid given the details.
King Boo's feat was literally translated as a body of space outside this world; the Illusion statement was a mistranslation iirc.
I'd prefer if someone liked Shiro looked at the translation and see if the translation from Weeb's friend is correct regarding the Mario 64 examples. But at the moment, that translation was the most reliable so far. But, creating a realm can create memories or history, and it's not like Bowser always controls the outcome of his creations. There existing Bob-Ombs on Mario's side doesn't contradict the possibility that he still created them. Lots of creator gods good and evil create people who are against them all the time. Furthermore,
Galaxy's lore regarding the Power Stars is very much canon to and gives more in depth context to the same Power Stars in Mario 64. The Lumas who turn into power stars are of an upper class than the ones who turn into planets, stars, comets, or galaxies. So even galaxy level power stars are actually believable given that lore alone. But, there are a total of 15 main courses, this doesn't include the minigames containing one power star also having Starry skies. Although, so far, the cage is the only one that didn't seem to have a legit starry sky, so that's more than 14 with starry skies using 120 Power Stars. Most of the main courses have 7 Power Stars in them.
Also, before anyone says realms "Are only painting size" actually the paintings themselves are merely portals as seen
here. The actual worlds it takes you to are legit massive worlds.
Also, I can agree that threads like this should preferably be refreshed.