Astrobot is anything but mediocre. That's not an opinion, it's a objective fact.
Exceptional music
Exceptional level design
Top tier physics, technically impeccable
Tons of variety in gadgets and gameplay
Some Pikmin's takes are hard to read.
As if Mario Oddysey or Bananza had any platforming challenge. If you want challenging and innovative platformers, just play Celeste, Motorslice or MIO.
The reason why Astrobot is so beloved it's because it's the ultimate ASMR game: its pleasant to the eyes, to the ears and to the touch. It's just a joy to play.