"I mean, the whole point is that uppon touching Pika once he will get paralysed and from that point on he becomes a punching bag."
Right and the paralysis isn't even that reliable nor is it guaranteed. You realize it's a 50/50 whether or not Static gets inflicted on you, then 25/75 in the chances it actually affects you from there, right? If we're going off initial percentages, that means for every eight moves, Boros would just be paralyzed once. That's literally just basic as hell statistics. It's not even represented like that in the Anime though, which depicts it as being far less likely. It takes one kick to send him to moon. Even then, the paralysis isn't remotely that could because it stops him for a few seconds max, not the entire match. You're completely misportraying how Static works. Also, you can literally break through it with enough willpower. Not only does Ash's Monferno do like 5 moves even after being paralyzed and moves around a lot (17:12 - onward), it outright ignores the paralysis with a determination not to lose (18:36). So unless you're telling me Boros is suicidal, he would literally just do the exact same thing.
"He literally did this only once and was his Ace, if he does some energy attack that isnt the star thingy then Pika can fight back with a thunderbolt and going by his higher AP he can gain that clash."
Again, you keep acting as if Pikachu can just negate any sort of pain it takes. The literal problem with Pikachu is that its only practical defense would be those electric attacks. And if it has to put out large amounts of them just to stop Boros from approaching, all that does is drain its stamina more significantly and make it harder to fight. You're unironically giving more reasons as to why Boros would be able to win such a fight because Pikachu just tires itself out even faster than what it would normally do against Boros. Not to mention Groudon is especially useless here and can't do much to help Pikachu given it's primarily use land-based abilities.
"Doesn't he has tackle, iron tail, headbutt, double edge, any other normal attack almost any pokemon can do?"
From how Pikachu's moves operate, no, it no longer knows such moves. And again, Pikachu would be far more prone to trying to keep a distance between him and Boros with electric moves if anything. Those moves are move CQC for Pikachu which aren't going to be all that helpful if Pikachu can't remotely control its mobility in the air.
You should also specify who you're replying to as the last response is from a different user and it makes it seem like those were my points.