Ace-Barn
#Tokio&Nickit
Don't remember, but either way the whole argument that this franchise desperately needs Ash's Pikachu to be showcased all the time is based on nothing.
It is amazing how much they push Pikachu. Not only is he the main characters primary pokemon that gets most of the battle and slice of life focus, he is never in his pokeball, he does the title screen for each episode, who's that pokemon around the commercials, is there to introduce the preview for the next episode, has more of a "voice" than the majority of pokemon, and even has a distinct running sound.
Which isn't me saying that Pikachu is the most popular, but it shocked me coming back to the series how many little ways they reinforce Pikachu as the mascot.