Sonic Adventure literally was the last game where Tails used brawn to fight instead of his technology/his friends/running away.

Tails still faced his fears in those games. Mech or no, weapons or no, friends or no, he faced his fears. His entire character is ABOUT facing his fears and self doubt, to step out of the role of player 2/sidekick to become a hero Sonic's equal. That bit in SA2 where he stands up to Eggman after thinking Sonic dead? The culmination of every bit of characterization for Tails starting with Sonic 2.

People like to stick up for this moment, to say that it's because he was traumatized, or that he's a kid, or that he didn't have his tech (which, given that he's not playable in Forces anyway, is a pitiful excuse. He's in a cutscene, they could've just put him in the fucking mech and had him fight Chaos until Classic showed up to help, bare minimum, it wouldn't affect gameplay or the story as a whole, it just wouldn't ruin Tails' character), but that has NEVER. STOPPED. HIM.

/r/SonicTheHedgehog Thread Link - i.redd.it