So I was bored and decided to read the dex entries to the Mega Evolutions of Pokemon

>Mega Aerodactyl: When it Mega Evolves, it becomes more vicious than ever before. Some say that's because its excess of power is causing it pain.
>Mega Lucario: It readies itself to face its enemies by focusing its mental energies. Its fighting style can be summed up in a single word: heartless.
>Mega Scizor: The excess energy that bathes this Pokémon keeps it in constant danger of overflow. It can't sustain a battle over long periods of time.
>Mega Garchomp: Its vaunted wings become scythes, sending it mad with rage. It swings its scythes wildly and slices the ground to pieces.
>Mega Slowbro: All the energy from Mega Evolution poured into the Shellder on its tail, leaving Slowpoke to be swallowed whole.
>Mega Gyarados: Mega Evolution also affects its brain, leaving no other function except its destructive instinct to burn everything to cinders.
>Mega Salamence: Mega Evolution fuels its brutality, and it may even turn on the Trainer who raised it. It's been dubbed "the blood-soaked crescent."
>Mega Kangashan: Thanks to Mega Evolution, its child grows. But as the child is good only at fighting and nothing else, its mother feels uneasy about its future.
>Mega Metagross: Mega Evolution stimulated its brain. It emerged as a ruthless Pokémon that will clutch at any means of ensuring its victories.
>Mega Glalie: It envelops prey in its mouth, freezing them instantly. But its jaw is dislocated, so it's unable to eat them.

I get that the dex entries in Sun and Moon have kinda messed up summaries in general. But there's this recurring theme among the mega Pokemon that exclaim that they all go through some degree of pain upon transforming as if Mega Evolution was bad for the Pokemon. Am I the only one who feels this way?