i think his flame reaction also affected his internal organs and stuff thats why endeavor didn’t envourage it and stopped it but toya like endeavor said inherited his stubbornness
fuyumi would be able to help him with maybe vooling him down but ice can’t treat fire burns it could do more harm than good
they also might have looled at shoto as also a way to maybe discourage toya
and somehow i dont believe endeavor actually gave toya yo the bero commission maybe he was forced to do if aftef he saw toya couldnt control his flames and sough the help of ogher professionals
Touya and Fuyumi could have made the perfect hero duo. When they notice him getting too hot she could prevent him from overheating and burning himself