I think Byleth is healthy and may introduce a new playstyle

[Goldschuss]

Traditionally in the Smash Bros. games, rushdown or combo characters with high speed have always been the most viable characters.
Slow characters, especially heavies, mostly got the short stick of the end. This changed somewhat in ultimate by reducing lag across the board, but Byleth is something entirely new.

Byleth is a slow character but still very viable in my eyes - If you change your playstyle accordingly. This time it isn't about rushing down your opponent and it might be the first time that a character gets the most use out of the opposite: Defensive ranged play.
While you could argue that this exists with the Belmonts already in the form of Projectile and holy cross spam, it only really compliments their kits. Byleth however, seems to be all about keeping your opponents at range, waiting for them to make a mistake.

This is not something I've ever seen in other Smash titles. And personally, I'm thrilled to see how tourneys will play out in the future, when the matchups won't be always fast vs fast characters. What do you think about this?

 

[Nah]

There's been highly viable defensive characters in the series and even in Smash Ultimate, and Byleth's not even an entirely new character archetype, so there's nothing new here?

 

[Arrei]

The problem I've got with this evaluation is that it doesn't even seem like Byleth's defensive capabilities are the best of their kind. Zoners already exist and are already a defensive archetype by their nature, Byleth's distinction is that they have incredible kill power if they can keep their opponent in that midrange danger zone, with a dash of classic heavy archetype in close quarters if you let them pull out a Dsmash or Dair on a weakened shield. But with a bad projectile, and the Belmonts having their Ftilt and side aerials which have more reach and safety on top of their own projectile kit, I don't think Byleth's defensive play is anything groundbreaking, especially when their focus on being powerful means their defensive play is frequently unsafe.

 

[The Rhythm Theif]

Traditionally in the Smash Bros. games, rushdown or combo characters with high speed have always been the most viable characters.
Slow characters, especially heavies, mostly got the short stick of the end. This changed somewhat in ultimate by reducing lag across the board, but Byleth is something entirely new.

Byleth is a slow character but still very viable in my eyes - If you change your playstyle accordingly. This time it isn't about rushing down your opponent and it might be the first time that a character gets the most use out of the opposite: Defensive ranged play.
While you could argue that this exists with the Belmonts already in the form of Projectile and holy cross spam, it only really compliments their kits. Byleth however, seems to be all about keeping your opponents at range, waiting for them to make a mistake.

This is not something I've ever seen in other Smash titles. And personally, I'm thrilled to see how tourneys will play out in the future, when the matchups won't be always fast vs fast characters. What do you think about this?

I approve of what has been said.