The champion in is a warrior specialization focused on boosting defenses and focusing offensive power through counterattacks.
It's been around since the first Dragon Age game and has been popular among players. This is because it's not too focused on anywhere specifically and creates an incredibly strong tank.
Veilguard has added a lot of interesting and unique specializations that go pretty far, but the champion is still the best at creating a reliable tank build.
Every other Warrior specialization has switched out or come and gone, but the champion remains. The champion uses their shield a lot, but they've become more offensive.
Like other specializations, this build in in does not limit players to one playstyle but gives them a better way to fight. With the addition of fire-based attacks, champions have become pretty overpowered, but only when you use them effectively.